Page:The Geologist, volume 5.djvu/148

124 organism, of the grade of structure of a germ-cell, may not arise by a collocation of particles through the operation of a force analogous to that which originally formed the germ-cell in the ovarian stroma, is a question worthy all care and pains in its solution. Pouchet has contributed valuable evidence of such production, under external influences, of species of Protozoa. With regard to the species of higher organisms, distinguishable as plants and animals, their origin is as yet only matter of speculation."—Palæontology, 2nd ed., pp. 18 and 441.

In these liberal and advanced sentiments, we must cordially concur. We recommend our readers to examine M. Pouchet's work carefully, and, if possible, to test his experiments over again. English minds too often exhibit an excessive reluctance to truths which on the Continent have been generally accepted. Trusting that this work may receive "a fair field and no favour," we conclude our remarks, with the hope that many more volumes of equal scientific importance may proceed from the gifted pen of the Director of the Museum of Natural History at Rouen.

The genus Cainotherium was founded by Bravard in the year 1835. Since his time it has received the following names:—Cyclognathus, Geoffroy St. Hilaire, 1835; Microtherium, Herm. von Meyer, 1837; Oplotherium and Plectognathus, Laizet and De Parieu, 1838; whilst the characteristically synthetic mind of De Blainville reunited it to the genus Anoplotherium, under the title of latecurvatum.

Gervais says it is probable that many species, and not one only, can be recognized amongst the remains which have been discovered, and that this conclusion has been admitted by all palæontologists who have studied these small pachyderms.

Pomel urges strongly the necessity of distinguishing many species among the Cainotheria, properly so called. He excludes from this genus the C. Courtoisii, which he erects into a type apart (Hyægulus). Gervais, on the contrary, gives merely to the genus Cainotherium a subgeneric value, subordinating it to Dichobune in his system. M. Pomel does not give any certain characters by which his five species can be distinguished. I translate his characters, such as they are:—