Reports and Proceedings — Geological Society of London. 41 



Frencli Lycees\ that it is addressed ; for elementary though these 

 "Notions generales" be, a trained judgment is yet required in order 

 to understand them properly. The practical acquaintance with the 

 nature of rocks, with the natural phenomena of the present day, etc., 

 acquired by these young men in the lower forms, would thus in the 

 higher classes receive a complement of the highest interest, and such 

 as to awaken in these young intellects wide horizons of thought." 



The book, in fact, is a brief and clear exposition of the great 

 truths of geology, in which all details are omitted except such as 

 have been with great judgment selected to illustrate each step of 

 the well-reasoned whole. These illustrations are naturally taken, 

 when possible, from French geology ; but with some slight altera- 

 tions, in this particular only, the work might with advantage be 

 translated into English. There are in this country many well- 

 educated persons who are above the standard of our many primers, 

 who do not care to wade through the dreary technicalities of the 

 larger text-books, and to whom the style of so-called "popular" 

 books is anything but attractive. Many readers of this class would 

 welcome a short account of the aims and methods of modern geology, 

 of its proved facts and probabilities, written by the hand of a master. 

 Professor Hebert's scholarly and most readable essay would, in our 

 opinion, exactly meet this case. GAL 



laSI^OIiTS -A-IsTX) :PS,0C:H3EJDI3^C3-S. 



Geolo&ical Societt op London. 



L— November 21, 1883.— J. W. Hulke, Esq., F.E.S., President, in 

 the Chair. — The following communications were read : — 



1. " On the Skull and Dentition of a Triassic Mammal (Tritylodon 

 longcevus, Ow.) from South Africa." By Prof. Owen, C.B., F.Pt.S. 



The specimen described in this paper formed part of a collection 

 containing remains of some of the known South-African Triassic 

 Keptilian genera, and agreed with them in its mode of fossilization. 

 It was-submitted to the author by Dr. Exton, of Bloemfontein. The 

 specimen is a nearly entire skull, wanting only the hinder part, and 

 it measures about 3| inches in length, from the broken end of the 

 parietal crest to the point of the united premaxillaries. The upper 

 surface shows the anchylosed calvarial portions of the parietals, 

 and the frontal bones divided by a suture ; the contiguous angles of 

 these four bones are cut off, so as to leave an aperture, occupied by 

 matrix, which may be a fontanelle, or a pineal or parietal foramen. 

 The frontals form the upper borders of the orbits, which are bounded 

 in front by the lacrymal and malar bones, and were not completed 

 behind by bone. Each frontal is narrowed to a point at the suture 

 between the nasal and maxillary. The nasals are narrow, but widen 

 in front to form the upper border of the exterior nostril, which is 

 terminal, and is completed by the premaxillaries. The maxillaries 

 are widened posteriorly, then constricted, and again widened before 

 their junction with the intermaxillaries. 



