scholarly journals VI.—On the Muscular Impressions of Cœlonautiluscariniferus J. de C. Sowerby, sp., compared with those of the Recent Nautilus

1889 ◽  
Vol 6 (11) ◽  
pp. 494-498 ◽  
Author(s):  
Arthur H. Foord ◽  
G. C. Crick
Keyword(s):  
British Museum ◽  
The Body ◽  
Body Chamber ◽  
Carboniferous Limestone ◽  
Shell Muscles

In examining the remarkably fine series of examples of Cœlonautilus cariniferus, mostly from the Carboniferous Limestone of Ireland, contained in the Geological Collections of the British Museum (Nat. Hist.), some were found to exhibit upon the cast of the body-chamber distinct marks of the shell-muscles. In one specimen (No. 50190) these are so perfect as to give a very clear outline of their form, and some of the test having been removed, their entire course can be made out.

VI.—Note on Ephippioceras clitellarium, J. de C. Sowerby, sp., and E. costatum, A. H. Foord

1900 ◽  
Vol 7 (12) ◽  
pp. 560-561
Author(s):  
G. C. Crick
Keyword(s):  
New Species ◽  
New Genus ◽  
British Museum ◽  
Acute Angle ◽  
The Body ◽  
Museum Collection ◽  
Body Chamber ◽  
Coal Measures ◽  
A New Species

The name Nautilus clitellarius was given by J. de C. Sowerby to a Nautiloid from the Coal-measures, Coalbrookdale, Shropshire, and the description was accompanied by three figures, each representing a different specimen. In 1884 the species was included by Professor Hyatt in his new genus Ephippioceras. In 1891 Dr. A. H. Foord found a new species, Ephippioceras costatum, which was said to be “distinguished from E. clitellarium (to which it is, however, very closely related) by the character of the septa and by the surface ornaments. The septa in E. costatum do not form such an acute lobe upon the periphery as do those of E. clitellarium, and they are also a little wider apart in the former species than they are in the latter. Moreover, E. costatum is provided with prominent transverse costæ, which are strongest upon the sides of the shell where they swell out into heavy folds. These costæ are directed obliquely backwards, and cross the septa at an acute angle, passing across the periphery and forming a shallow sinus in the middle. None of the specimens in the British Museum have the test preserved, so that the ribbing has only been observed upon casts. The costæ are equally well developed upon the body-chamber and upon the septate part of the shell in the adult, but they were either very feeble or altogether absent in the young.” A re-examination of the specimens in the Museum collection shows that the separation of the two forms is quite justifiable.

III.—On a Deformed Example of Hoplites Tuberculatus, J. Sowebby, sp., from the Gault of Folkestone

1898 ◽  
Vol 5 (12) ◽  
pp. 541-542 ◽  
Author(s):  
G. C. Crick
Keyword(s):  
New Species ◽  
Short Note ◽  
British Museum ◽  
The Body ◽  
Museum Collection ◽  
Body Chamber ◽  
A New Species

There has recently been presented1 to the British Museum collection an Ammonite from the Gault of Folkestone that seems to be worthy of a short note. It is represented in the accompanying figures. At first sight it appears to be a new species. The shell is nearly complete and exceedingly well preserved; there has evidently been another half whorl to the specimen (see Fig. a), but this, which apparently constituted the body-chamber, has been broken away, leaving at the anterior end of the specimen the surface of the last septum.

IV.—Notes on the Cephalopoda Belonging to the Strachey Collection from the Himalaya. Part I: Jurassic

1904 ◽  
Vol 1 (3) ◽  
pp. 115-124 ◽  
Author(s):  
G. C. Crick
Keyword(s):  
Anterior Part ◽  
British Museum ◽  
The Body ◽  
Museum Collection ◽  
Body Chamber ◽  
The Himalaya ◽  
Lateral Area ◽  
Outer Half

According to Professor Blanford the only example of this species in the Straehey Collection was the fragment which he figured. This is now in the British Museum collection [No. C. 5045]; it was transferred from the Museum of Practical Geology, labelled with one of that Museum's labels “Oolitic: Niti Pass. Ammonites scriptus (Stra.). Coll. by Col. Strachey.” The figures, which are all reversed, are not good. The portion of the fossil that is figured is entirely septate; the anterior part of the specimen that formed the base of the body-chamber is not included in the figure, nor does the figure show the shorter intermediate ribs which extend over the outer half of the lateral area of the whorl.

On the Amphilaphorchidinae, A New Subfamily of Proteocephalid Cestodes, and Myzophorus admonticellia, gen. et sp.n., Parasitic in Pirinampus spp. from the Amazon

Parasitology ◽  
1934 ◽  
Vol 26 (1) ◽  
pp. 141-149 ◽  
Author(s):  
W. N. F. Woodland
Keyword(s):  
British Museum ◽  
The Body ◽  
Entire Body ◽  
Adipose Fin ◽  
General Appearance

“Piranabú,” “Piranampú” or “Piranampú” (the last according to Goeldi, 1898) are local names on the Amazon applied to the siluroid fish which, so far as it is possible to determine from memory and from the rough sketches and notes which I made at the time, is the modern Pirinampus pirinampus (Spix). This fish, of which I examined eight examples, attains a length of at least 60 cm., has an elongated adipose fin more than one-third the length of the entire body, microscopic scales, possesses maxillary barbels about half the length of the body, and in general appearance closely resembles the figure (Tab. VIII, a) of “Pimelodus ctenodus” provided by Spix (1829). I am much indebted to Mr J. R. Norman, of the British Museum, for his kind assistance in identification.

IV.—The Rotiform Bryozoa of the Isle of Wight

1907 ◽  
Vol 4 (10) ◽  
pp. 442-443 ◽  
Author(s):  
J. W. Gregory
Keyword(s):  
British Museum ◽  
The Body ◽  
Isle Of Wight ◽  
Shaped Body ◽  
Outer Corner ◽  
Preliminary Account

A Small fossil with a wheel-shaped body borne on a narrow stem has long been known from the base of the Holaster planus zone in the Isle of Wight. It has been recognized as one of the Bryozoa, but has not been described, although once recorded as “near Defrancia diadema, Hag.” It has also been recorded by Dr. A. W. Rowe as “the beautiful little rotiform Bryozoon.”The following diagnosis has been lying unpublished for eight years in the manuscript of the second volume of the Catalogue of Cretaceous Bryozoa in the British Museum. A preliminary account of the species is now issued, as the name is wanted for reference in the course of Dr. A. W. Rowe's forthcoming memoir on the Chalk of the Isle of Wight. A fuller account of the species with illustrations, on plates drawn in 1900, will be given in the Catalogue, which it is hoped will be issued during this Winter.Blcavea Rotaformis, n.Sp.Diagnosis.—Zoarium simple or compound, with a narrow cylindrical stem, attached in a circular concavity in the lower part of the body. The body of the zoarium is discoid, or wheel-shaped, and has on the margin a series of vertical radial projections like cog-wheels. The cogs usually project for a distance nearly equal to the radius of the disc. The cogs may be prolonged at their upper, outer corner into spike-like fasciculi. The upper surface between the bases of the fasciculi is depressed, and occupied by the small, crowded, irregular apertures of the intermediate, subordinate zoœcia.

Jaws and radula of the Carboniferous ammonoid Cravenoceras

1995 ◽  
Vol 69 (4) ◽  
pp. 703-707 ◽  
Author(s):  
Kazushige Tanabe ◽  
Royal H. Mapes
Keyword(s):  
The Body ◽  
Anterior Portion ◽  
Phylogenetic Affinity ◽  
Body Chamber ◽  
Lower Jaw ◽  
Upper Jaw ◽  
Marginal Plates ◽  
Buccal Space

A well-preserved mouth apparatus consisting of jaws and a radula was found in situ within the body chamber of the goniatite Cravenoceras fayettevillae Gordon, 1965 (Neoglyphiocerataceae: Cravenoceratidae), from the middle Chesterian (Upper Mississippian) of Arkansas. Both upper and lower jaws consist of a black material. The lower jaw is characterized by a widely opened larger outer lamella and a shorter inner lamella. The upper jaw is fragmental. The radula is preserved in the anterior portion of the buccal space and comprises a series of tooth elements. Each transverse tooth row consists of seven teeth (a rhachidian and pairs of two lateral and one marginal teeth), with a pair of marginal plates. This arrangement is typical of radulae of other ammonoids of Carboniferous to Cretaceous age, coleoids, and the orthoconic “nautiloid” Michelinoceras (Silurian, Michelinocerida), suggesting a phylogenetic affinity among them.

Form and function of orthoconic cephalopod shells with concave septa

Paleobiology ◽  
1977 ◽  
Vol 3 (3) ◽  
pp. 300-321 ◽  
Author(s):  
G. E. G. Westermann
Keyword(s):  
Calcium Carbonate ◽  
Relative Length ◽  
The Body ◽  
Neutral Buoyancy ◽  
Spherical Cap ◽  
Apical Angle ◽  
Form And Function ◽  
Body Chamber ◽  
Septal Thickness ◽  
Horizontal Stability

Models of “ideal” orthoconic shells having simple concave septa with minimal weight and maximal strength and analysis of 72 species of fossil orthocones and cyrtocones yield important insights into the physical principles underlying cephalopod shell design. The ideal septum is a spherical cap weighing only 77% of a hemispherical septum of equal strength. The septa of most longicones approximate this ideal shape while those of brevicones are less curved, probably owing to buoyancy problems. Increase in septal strength leads to weight increase unless the shell becomes more logiconic or septal spacing increases or both. However, increased spacing requires more cameral liquid for septum formation, thus reducing buoyancy. In ideal longicones, septal spacing resembles the cone radius for thick, strong septa but declines to half of the cone radius for thin, weak septa. In ideal intermediates and brevicones, spacings are respectively reduced by factors of about 2 and 4, with similar additional dependence on septal thickness. Most real septa resemble these ideal models.The relative length of the body chamber to the phragmocone varies greatly between about 0.2 and 1.5, depending mainly on the wall thickness and to a lesser degree on the septal thickness, apical angle and body density. Removal of cameral liquid in the adult must be compensated for by additional growth to retain neutral buoyancy. The conditions for neutral equilibrium calculated for longicones with different “counterweights” indicate that: (1) cameral liquid only is least feasible; (2) half-and-half calcium carbonate and liquid results in one-third length and one-quarter volume reduction of the body chamber; (3) with calcium carbonate only, body chamber reduction is minimal. Real ‘counterweights’ appear to be intermediate between (2) and (3), providing the animal with horizontal stability, which is missing in (3). Most uncalcified siphuncles reduce the body chamber only slightly although they improve horizontal stability. If the wall attains full thickness only at the apical end of body chamber, the liquid-only ‘counterweight’ becomes feasible.

New Pennsylvanian coleoids (Cephalopoda) from Nebraska and Iowa, USA

2017 ◽  
Vol 92 (2) ◽  
pp. 146-156 ◽  
Author(s):  
Royal H. Mapes ◽  
Larisa A. Doguzhaeva
Keyword(s):  
New Species ◽  
New Genus ◽  
The Body ◽  
New Genera ◽  
Shell Material ◽  
Body Chamber ◽  
Evolutionary Radiation

AbstractFour rare Pennsylvanian (Stark Shale: Pennsylvanian, Missourian [=Kasimovian]) coleoids from Nebraska and Iowa, which are preserved as flattened partial phragmocones and body chambers associated with three-dimensionally fossilized ink sacs, are herein described as Pabianiconus starkensis new genus new species, Nebraskaconus whitei new genus new species, and Starkites compressus new genus new species. One specimen that is missing most of the phragmocone, is provisionally assigned to Donovaniconus. The fossils are assigned to the Coleoidea because of the presence of ink-filled sacs in the body chamber region of the conch. Additionally, eight fragmented and flattened phragmocones and body-chamber clusters with similar morphologies, including some with ink fragments and arm hooks, are assigned to the Coleoidea, but are not named because of their fragmentary condition. On most of the eight specimens, the shell material is associated with other unidentified finely macerated material, which suggests these fossils are probably either ejectoid masses or coprolites from coleoid predators and/or scavengers. However, the new genera named above appear to have been deposited as complete animals, based on the presence of the ink-filled sacs that are in the body chambers. With their body chamber and phragmocone morphologies, these rare coleoid taxa provide valuable information about conch variability within the Carboniferous evolutionary radiation of coleoids.

Mosasaur tooth marks on the ammonite Placenticeras from the Upper Cretaceous of Alberta, Canada

1990 ◽  
Vol 27 (3) ◽  
pp. 469-472 ◽  
Author(s):  
R. A. Hewitt ◽  
G. E. G. Westermann
Keyword(s):  
Upper Cretaceous ◽  
The Body ◽  
Shell Wall ◽  
Flexible Support ◽  
Body Chamber ◽  
Tooth Marks

Mosasaur tooth marks were found in the body chamber and phragmocone of the Campanian ammonite Placenticeras meeki Boehm from the Bearpaw Formation of the St. Mary River area near Lethbridge. They imply that the shell wall of the ammonite buckled around point loads and did not break into fragments like the shell of Nautilus. The complex septal sutures provided a strong but marginally flexible support for the shell wall. The shells were probably attacked near the surface, perhaps during initial postmortem drift of corpses.

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