scholarly journals LIFE-HISTORY OF LYDA FASCIATA (NORTON), FAM. TENTHREDINIDÆ

1902 ◽  
Vol 34 (8) ◽  
pp. 214-216
Author(s):  
Richard. F. Pearsall
Keyword(s):  
Life History ◽  
Coming Out ◽  
Wild Cherry ◽  
The Earth ◽  
History Of ◽  
Deep Green

Full-grown larvæ were taken on wild cherry (Prunus) in the latter part of September, 1901. Placed in a box over earth, they fed but a day or two, truned a deep green, and entering the earth two to three inches, formed rounded cells, in which they remained as larvæ all winter, transforming to pupæ just before emergence. They are gregarious, remaining in their web, filled with its mass of exuvia, untill full-grown, when, as their growth is completed, individually they drop from it and enter the ground. One which was kept under observation formed a pupa on April 28th, and emerged eight days thereafter. The pupal skin is very thin, showing distictly the parts of the enclosed imago. This brood commenced emerging April 25th, and a few individuals are still coming out, May 31st. In the eariler days the males predominated, later the females, Altogether, 134 males and 123 females have appeared. Copulation took place at once, the pair remaining in coitu from three to five hours.

II. Note on Professor Hull’s paper

1887 ◽  
Vol 42 (251-257) ◽  
pp. 308-310
Keyword(s):  
Life History ◽  
Sea Water ◽  
Chemical Change ◽  
The Earth ◽  
Organic Body ◽  
History Of

Dr. Alleyne Nicholson, a palæontologist of no small repute, refers to this subject in his work on the ‘ Ancient Life History of the Earth,’ p. 34. He considers that the silica which has surrounded and infiltrated the fossils which flint contains, must have been deposited “from sea-water in a gelatinous condition, and subsequently have hardened.” Also that “the formation of flint may therefore be regarded as due to the separation of silica from sea-water, and its deposition round some organic body in a state of chemical change or decay.”

scholarly journals I.—American “Surface Geology,” and its Relation to British. With some Remarks on the Glacial Conditions in Britain, especially in Reference to the “Great Ice Age” of Mr. James Geikie

1877 ◽  
Vol 4 (11) ◽  
pp. 481-496
Author(s):  
Searles V. Wood
Keyword(s):  
United States ◽  
Life History ◽  
North America ◽  
The United States ◽  
Ice Age ◽  
The Earth ◽  
The World ◽  
History Of ◽  
The Rich ◽  
Surface Geology

From no part of the world have we of late years derived more additions to the Geological Record than from North America. Besides important additions to the earliest pages of that record, the rich collections made by the United States Surveyors, both of fauna and flora, from the Cretaceous, Eocene, and Miocene deposits, have thrown much light upon the life history of the Earth; and it is even contended that they have bridged over the interval which, notwithstanding the Maestricht beds, the Pisolitic, and the Faxoe Limestones, still remains sharply marked between the Cretaceous and Tertiary formations of Europe so far as they have yet been examined.

scholarly journals Trophic interactions and biodiversity: How natural enemies shape biodiversity: a double-edged sword

2018 ◽  
Author(s):  
Alexandre Mestre ◽  
Robert D. Holt
Keyword(s):  
Life History ◽  
Natural Enemies ◽  
Adaptive Radiation ◽  
Trophic Levels ◽  
Substantial Portion ◽  
Top Down ◽  
The Earth ◽  
Biodiversity Preservation ◽  
History Of ◽  
Regulation Mechanisms

Natural enemies, that is, species that inflict harm on others to feed on them, are fundamental drivers of biodiversity dynamics and represent a substantial portion of it. Along the life history of the Earth, natural enemies have been involved in probably some of the most productive mechanisms of biodiversity genesis; that is, adaptive radiation mediated by enemy-victim coevolutionary processes. At ecological timescales, natural enemies are a fundamental piece of food webs and can contribute to biodiversity preservation by promoting stability and coexistence at lower trophic levels through top-down regulation mechanisms. However, natural enemies often produce dramatic losses of biodiversity wherein, in most cases, humans take part of it.

VI.—A Contribution to the Life-History of Bowenia

1926 ◽  
Vol 54 (2) ◽  
pp. 357-394 ◽  
Author(s):  
A. Anstruther Lawson
Keyword(s):  
Life History ◽  
Geographical Distribution ◽  
Great Powers ◽  
Land Plants ◽  
Long Period ◽  
Wide Geographical Distribution ◽  
The Earth ◽  
History Of

The existing Cycads, with their nine genera and about eighty known species, represent the last lingering survivors of an ancient race that existed in Mesozoic times. There is very little evidence of their geological and geographical distribution throughout that great period; but it seems that up to the close of the Cretaceous they constituted an important feature of the Land Vegetation, with the Bennettitales, Ginkgoales, and Coniferales as their contemporaries. During that long period they were probably represented by many genera and species, and apparently enjoyed a very wide geographical distribution. The nature of their seed as an organ of reproduction seems to have endowed them with great powers of propagation and dissemination, which enabled them to spread over the earth and to occupy dry soils which probably had never before been occupied by Land Plants.

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