scholarly journals XIX. The Croonian lecture - Observations on the locomotor system of echinodermata

1881 ◽  
Vol 172 ◽  
pp. 829-885 ◽  
Keyword(s):  
Short Distance ◽  
Body Cavity ◽  
The Body ◽  
Considerable Time ◽  
Locomotor System ◽  
Plaster Of Paris ◽  
Respiratory Tree ◽  
Space Plate ◽  
Stone Canal ◽  
Brick Dust

1. Holothuria.— When a longitudinal incision is made through the perisome of a Holothurian ( Holothuria communis ) there is generally seen escaping, along with the branches of the respiratory tree and genital gland, a long sacculated tube filled with a fluid, and holding in suspension a large quantity of a brick-dust coloured pigment. This tube, which may be one-and-a-half times the length of the entire animal, and from one line to half-an-inch in diameter, is the polian vesicle (Plate 79, fig. 1, a ). On following it upwards it is found to open freely into a wide circular canal (Plate 7 9, fig. 1, b ) a short distance from the termination of the stone canal. From this circular canal five lozenge-shaped sinuses (Plate 79, fig. 1, c ) project forwards, and from each of these two large oval sinuses (Plate 79, fig. 1, d ) run forwards parallel with each other, the ten oval sinuses becoming continuous with the hollow stems of the tentacles (Plate 79, fig. 1, e ). In a Holothurian 8 inches in length, exclusive of the tentacles, the lozenge-shaped sinuses, which may be designated the sinuses of the circular canal, measure a quarter of an inch from above downwards and a little more from side to side. From around the pointed upper ends of the canal sinuses the five longitudinal muscular bands take their origin. When a solution of Berlin blue is injected into the polian vesicle, the circular canal and its sinuses, the oval sinuses and tentacles, the radial canals, pedicels and ampullæ are rapidly distended; but, unless the pressure be kept up for a considerable time, none of the coloured fluid penetrates into the stone canal, and either the vesicle, ring, or one of the sinuses gives way before it reaches the madreporic plate. If one of the radial canals be divided while the injection is being proceeded with, the coloured fluid at once escapes, and the tension within the polian vesicle, the circular canal, and the tentacles is diminished. If plaster of Paris be substituted for the solution of Berlin blue, a cast is readily obtained of the circular canal and its sinuses, but the plaster does not find its way either into the sinuses of the tentacles or into the radial canals. When, however, a coloured solution of gelatine is forced into the polian vesicle, the tentacles and their sinuses, the radial canals, ampullæ, and pedicels are filled, as well as the circular canal and its sinuses. Examination of specimens injected with plaster of Paris and gelatine shows the circular canal to be a quarter of an inch in diameter, and to communicate freely both with the polian vesicle and with the lozenge-shaped sinuses springing from it. The specimens injected with a gelatine mass further show that each canal sinus opens into a cæcal tube, which runs forward internal to the sinuses of the tentacles as far as a wide circum-oral space (Plate 79, fig. 2, a ). This space communicates by well-defined apertures (Plate 79, fig. 3, b ), with that portion of the body cavity which lies between the sinuses and the œsophagus, and which is reached through the circular apertures between the sinuses of the circular canal (Plate 79, fig. 1, f ).

scholarly journals I. The Croonian lecture. —“ Observations on the locomotor system of echinodermata

1881 ◽  
Vol 32 (212-215) ◽  
pp. 1-11 ◽  
Keyword(s):  
Short Distance ◽  
Body Wall ◽  
Body Cavity ◽  
The Body ◽  
Considerable Time ◽  
Tube System ◽  
Radial Canal ◽  
Locomotor System ◽  
Direct Pressure ◽  
Stone Canal

In Holothuria the polian vesicle opens freely into a wide circular canal a short distance from the termination of the stone canal. From this circular canal five lozenge-shaped sinuses project forwards, and from each of these two large oval sinuses run forward parallel with each other─the ten oval sinuses becoming continuous with the hollow stems of the tentacles. Injection of the polian vesicle shows that it forms one continuous tube system with the circular canal and its sinuses, oval sinuses and tentacles, ampullæ and pedicels. Unless the pressure is kept up for a considerable time there is no penetration of the injected fluid into the stone canal, and either the ring, the vesicle, or a sinus gives way before the fluid reaches the madreporic plate. Specimens injected with a gelatine mass show that each canal sinus opens into a cæcal tube, which runs forwards internal to the sinuses of the tentacles as far as a wide circum-oral space. This space communicates by well-defined apertures with that portion of the body cavity which lies between the sinuses and the œsophagus, and which is reached through the circular apertures between the sinuses of the circular canal. Each canal sinus has three other apertures in its walls. It opens by a small round aperture into a radial canal, and the two other apertures occur as minute slits, one at each side of the orifice of the radial canal leading into the adjacent tentacle sinuses. When the tentacle into which the sinus opens is protruded, there is no constriction between the sinus and the tentacle ; but when the ten­tacle is retracted, there is a well-marked constriction at the junction of the sinus with the tentacle. The eversion of the perisome and the protrusion of the tentacles are effected chiefly by the shortening of the polian vesicle and the constriction of the longitudinal muscular bands, which run from the inner surface of the body wall between each two adjacent tentacle-sinuses ; but the circular fibres of the body wall also assist in the process by contracting immediately behind the group of sinuses, so as to act on them by direct pressure, and also indirectly by forcing the body fluid against them.

Myiasis in Bufo regularis caused by a Tabanid Larva

Parasitology ◽  
1924 ◽  
Vol 16 (1) ◽  
pp. 111-112
Author(s):  
Edward Hindle
Keyword(s):  
Fibrous Tissue ◽  
Dorsal Surface ◽  
Body Cavity ◽  
The Body ◽  
Careful Examination ◽  
Large Female ◽  
Considerable Time ◽  
Ventral Region ◽  
Cylindrical Structure ◽  
The Right

In December, 1922, whilst dissecting a large female example of Bufo regularis, one of my students noticed a cylindrical structure extending along the ventral region of the body-cavity. A careful examination showed that this structure consisted of an elongated sac-like diverticulum of the right lung, containing an almost full-grown specimen of a dipterous larva, which could be seen through the membraneous wall of the diverticulum. The base of the latter, in addition to its point of origin from the lung, was also connected to the dorsal surface of the liver by strands of fibrous tissue, suggesting that the growth had been in existence some considerable time in order to cause such adhesions. Posteriorly, the diverticulum hung freely in the body cavity and extended to the extreme hinder end. Its dimensions were 5·5 cm. in length, by 0·5 cm. in diameter, but tapering towards each extremity.

Degeneration of the Remaining Pronephros of Rana temporaria after Unilateral Pronephrectomy

Development ◽  
1962 ◽  
Vol 10 (2) ◽  
pp. 224-230
Author(s):  
H. Fox
Keyword(s):  
Rana Temporaria ◽  
Body Cavity ◽  
The Body ◽  
Considerable Time ◽  
Pronephric Duct

If a pronephric duct of a Triturus larva is blocked it degenerates behind the lesion (Fox, 1957). If in Bufo vulgaris japonicus tadpoles the nephrostomial tubules are extirpated, so that there is no continuity between the remainder of the pronephric tubules and the coelom, the pronephric tubules themselves will degenerate (Shimasaki, 1930). Furthermore, pronephric tubules of a young Axolotl larva grafted into the lateral flank of a similar host, when not in functional continuity with the coelom, are stunted and collapsed (Fox, 1960). Functional connexion of the pronephros and its duct with the body cavity is thus essential to maintain a normal expanded tubular condition. Nevertheless, normal pronephric degeneration of Rana, which commences atthe beginning of metamorphosis, precedes functional discontinuity, for the ronephric duct has a continuous lumen along its length and the nephrostomial tubules are open to the coelom for a considerable time after the onset of pronephros degeneration (Fox, 1962).

scholarly journals Memoirs: Planktothuria diaphana, gen. et sp. n

1920 ◽  
Vol s2-64 (255) ◽  
pp. 373-382
Author(s):  
J.D. F. GILCHRIST
Keyword(s):  
South African ◽  
The Body ◽  
The South ◽  
Respiratory Tree ◽  
Calcareous Deposits ◽  
Single Opening ◽  
Stone Canal ◽  
Dorsal Mesentery

1. A medusa-like Holothurian has been found off the South African coasts. 2. It is devoid of external podia. 3. Podia are found embedded in the thick gelatinous epidermis, and are arranged in three groups in the form of-- (1) Arms or oral podia forming a hood-like structure over the mouth, and supplied from the dorsal and ventrolateral radial canals. (2) Dorsal podia, which are slender and terminate in knobs. (3) Lateral podia towards the posterior end of the body. 4. Tentacles are supplied by the circular canal. 5. The stone-canal is single, and opens to the exterior by a single opening. 6. Calcareous deposits do not appear to occur in any part of the body, except in the form of small knobbed spheres round the oesophagus. 7. Respiratory tree and Cuvierian organ absent. 8. Gonads in two grape-like masses, one on each side of the dorsal mesentery, and opening to the exterior by a long, slender duct. Mature ova .3 mm. in diameter, and provided with, oil-globules. 9. It cannot be placed, in any of the known groups of Holothurians, chiefly on account of the origin of the tentacles from the circular canal.

ENCAPSULATION OF RHABDITOID NEMATODES IN MOSQUITOES

1962 ◽  
Vol 40 (7) ◽  
pp. 1269-1275 ◽  
Author(s):  
Joan F. Bronskill
Keyword(s):  
Aedes Aegypti ◽  
Endemic Species ◽  
Body Cavity ◽  
Fourth Instar ◽  
The Body ◽  
Histological Structure ◽  
Adult Tissue ◽  
Defence Reaction ◽  
Blood Sinus

In third and fourth instar larvae of Aedes aegypti (L.), juveniles of the rhabditoid, DD136, penetrate the blood sinus and cardial epithelium of the proventriculus to enter the body cavity of the host, where they complete their development. By 5 hours, a thick capsule developed about many of the ensheathed immature adults of DD136 within the body cavity of A. aegypti larvae. This rapid defence reaction of the mosquito to DD136, which has both a melanin and a cellular manifestation, occurs both in the exotic mosquito A. aegypti and in the two endemic species tested, Aedes stimulans (Walker) and Aedes trichurus (Dyar). The resistance of A. stimulans to an endemic rhabditoid, possibly of the Diplogasteridae, is also similar. The histological structure of the capsule is not affected during metamorphosis in A. aegypti; however, during histogenesis of adult tissue displacement and (or) distortion of some tissues and organs may be caused by the presence of the capsule within the host's body cavity. The activity of the adult A. aegypti is normal when this distortion or displacement is minor. Though usually encapsulated DD136 are retained within the body cavity of A. aegypti during metamorphosis, sometimes they are partially or completely expelled from the host's body cavity at the time of molting.

Studies on Tapeworm Physiology

1949 ◽  
Vol 26 (1) ◽  
pp. 1-15
Author(s):  
J. D. SMYTH
Keyword(s):  
Bacterial Infections ◽  
Detrimental Effect ◽  
Horse Serum ◽  
Body Cavity ◽  
The Body ◽  
Nutrient Media ◽  
Medium Strength ◽  
By Products ◽  
Histochemical Examination

1. Plerocercoid larvae of the pseudophyllidean cestode Ligula intestinalis from the body cavity of roach, were cultured in vitro at 40°C. in a variety of saline and nutrient media. About 65% of such cultures were aseptic. 2. During cultivation, larvae produced acid by-products (unidentified) and the pH fell rapidly. 3. The presence of these acid by-products slowed down development, or, if present in sufficient quantity, caused death. 4. In order to obtain development in nutrient media in a period (3 days) comparable to that required in a bird (the normal host) it was necessary to renew the medium 24-hourly. 5. 6% of the eggs produced from a worm cultured in horse serum were fertile. Fertile eggs were never obtained from larvae cultured in any other media. 6. Certain bacterial infections had no apparent detrimental effect on development, but others were toxic. 7. Some larvae underwent development in non-nutrient medium (¾ strength Locke's solution). The exact conditions under which this occurred was not determined. 8. Fragments (3 cm. long), of larvae or larvae with either scolex or posterior half removed, underwent development to the stage of oviposition in nutrient media. 9. Histochemical examination revealed that the plerocercoid larvae were almost fat-free. During cultivation, very large quantities of cytoplasmic fat were produced the quantity being proportional to the duration of cultivation. Fat was produced even under starvation conditions (i.e. during cultivation in saline) and can be considered a metabolic by-product. 10. The fresh plerocercoid contained great quantities of glycogen in the parenchyma and muscle regions. After cultivation in nutrient or saline media, considerable quantities were still present.

scholarly journals The occurrence of Contracaecum sp. larvae (Nematoda : Anisakidae) in the catfishClarias gariepinus (Burchell) from Lake Chivero, Zimbabwe

2004 ◽  
Vol 71 (1) ◽  
Author(s):  
M. Barson
Keyword(s):  
Significant Relationship ◽  
Condition Factor ◽  
Clarias Gariepinus ◽  
Parasite Prevalence ◽  
Body Cavity ◽  
The Body ◽  
Nematode Parasites ◽  
Significant Difference ◽  
Third Stage ◽  
Males And Females

Clarias gariepinus were collected from Lake Chivero, Zimbabwe, and examined for nematode parasites from November 2000 to May 2002. Of the 202 specimens collected, 42.6 % were infected with third-stage larvae of Contracaecum sp. in the body cavity. The intensity of the infection was 1-7 worms per fish (mean intensity = 2.2). Seasonal variation in the prevalence of the parasite was not obvious and there was no significant difference in the prevalence of infection between males and females (c2 = 2.228; P > 0.05). No significant relationship between host size and prevalence was established. There was also no significant relationship between intensity and the body condition factor (r = 0.11; P > 0.05). The low parasite prevalence may have been caused by the disruption of the infection cycle since piscivorous birds, which are the final hosts of the parasite, do not feed on C. gariepinus in Lake Chivero.

scholarly journals Studies of the Nucleopolyhedrovirus Infection Process in Insects by Using the Green Fluorescence Protein as a Reporter

1998 ◽  
Vol 72 (4) ◽  
pp. 3377-3382 ◽  
Author(s):  
John W. Barrett ◽  
Andy J. Brownwright ◽  
Mark J. Primavera ◽  
Subba Reddy Palli
Keyword(s):  
Fat Body ◽  
Secondary Infection ◽  
Green Fluorescence Protein ◽  
Body Cavity ◽  
Infection Process ◽  
The Body ◽  
Green Fluorescence ◽  
Temporal Regulation ◽  
Baculovirus Infection ◽  
Fluorescence Protein

ABSTRACT A recombinant Autographa californica multicapsid nucleopolyhedrovirus (AcMNPV) expressing the green fluorescence protein (GFP) under the control of the AcMNPV polyhedrin promoter was constructed to study the spatial and temporal regulation of baculovirus infection in a permissive host. Larvae that ingested AcMNPV-GFP showed localized expression of GFP in the midgut epithelial cells, as well as hemocytes, at 24 h postinfection. The presence of fluorescence in these tissues indicated not only that the virus was replicating but also that the very late viral proteins were being synthesized. Secondary infection occurred within the tracheal cells throughout the body cavity, confirming earlier reports, and these foci of infection allowed entry of the virus into other tissues, such as the epidermis and the fat body.

A study of the host relations of Halictophagus pontifex Fox (Strepsiptera), a parasite of Cercopidae (Hem., Aphrophorinae), in Uganda

1970 ◽  
Vol 60 (1) ◽  
pp. 33-42 ◽  
Author(s):  
D. J. Greathead
Keyword(s):  
Regression Analysis ◽  
Life Cycle ◽  
Multiple Regression Analysis ◽  
Multiple Regression ◽  
Population Data ◽  
Body Cavity ◽  
The Body ◽  
Density Dependent ◽  
Grassland Site ◽  
Host Relations

The relations of the Strepsipterous parasite Halictophagus pontifex Fox to seven species of its Cercopid (Aphrophorinae) hosts were studied at a grassland site in Uganda. Dissections of weekly samples of the Cercopids collected by sweeping showed that the duration of the life-cycle of H. pontifex is 30–40 days. The parasite is found only in adult hosts which can support as many individuals (up to 7) in Poophilus costalis (Wlk.) as can develop in the space available in the body cavity. Both the maximum number of parasites per host and the rate of parasitism are related to the volume of the host. Parasitism arrests development of the ovaries of female hosts; they may reproduce after emergence of male parasites but not after exhaustion of females because of reinfection by triungulins. Graphical and regression analysis of the population data (no. individuals/1 000 sweeps) show that, for P. costalis, parasitism by H. pontifex is density dependent and the chief regulating factor. Rainfall 58–64 days before sampling also was correlated with P. costalis density, but multiple regression analysis showed it to be insignificant.

scholarly journals Testicular Morphology and Sperm Motility in Cultured African Catfish (Clarias gariepinus) at Different Stages of Development

2016 ◽  
Vol 8 (3) ◽  
pp. 281-285 ◽  
Author(s):  
Chidozie Nwabuisi OKOYE ◽  
Udensi Maduabuchi IGWEBUIKE ◽  
Anietie Francis UDOUMOH ◽  
Chinadindu Tochukwu OKEREKE
Keyword(s):  
Sperm Motility ◽  
Clarias Gariepinus ◽  
Body Cavity ◽  
The Body ◽  
Sperm Cells ◽  
African Catfish ◽  
Testicular Weight ◽  
Testicular Morphology ◽  
The Mean ◽  
Somatic Index

Testicular morphology and sperm motility were evaluated in cultured Clarias gariepinus (n = 25) purposively assigned to five groups according to their age. The results showed that the testes were paired, elongated, dorso-ventrally flattened structures, situated in the caudal aspects of the body cavity. The mean length of both right and left testes increased linearly with age, being significantly (p < 0.05) higher at 6 months than at 4 and 5 months of age, and also significantly (p < 0.05) higher at 8 months than at 6 months of age, while the mean weight and organo-somatic index of the catfish testes increased linearly until 6 months of age, after which no significant (p > 0.05) increase in the testicular weight and organo-somatic index was observed. Unidirectional progressive movement of spermatozoa was detected in the milt of C. gariepinus at 6, 7 and 8 months of age, but sperm cells were non-motile at 4 and 5 months of age. Histological sections showed seminiferous lobules, whose germinal epithelia were characterized by many cysts enclosing clones of sperm cells. Each cyst enclosed a clone of sperm cells at an identical stage of spermatogenesis. Spermatids and spermatozoa were present in the lumen of the seminiferous lobule. The obtained results indicate that the morphology of the testes of C. gariepinus is similar to the testes of members of the order Siluriformes, but sexual maturity and production of motile spermatozoa may be achieved at 6 months of age in the African catfish.

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