I860.] Geology and Palceontology. 297 



The author ingeniously remarks that the head of the Dinotherium 

 being so aberrant, the animal might almost be expected to possess 

 other anomalous structures, and he suggests as an explanation of the 

 position of the " marsupial bones," that had they been attached to the 

 pubis the pouch would not have been large enough to receive the 

 young, while their articulation to the iliac bones sufficiently accounts 

 for the great lateral development of the latter. 



The Dinotherium was considered to be allied to the Tapirs, by 

 Cuvier ; it was afterwards thought to be a Cetacean, until the dis- 

 coveries of M. Lartet, when it took its place amongst the Pachyderms. 

 Now, if M. Solaro be right, it must be considered a Pachydermatous 

 Marsupial, approaching the Nototherium to some extent, but not in 

 respect of the position of the marsupial bones. Again, if M. Solaro 

 be right, the Dinotherium could not have been aquatic in its habits, 

 for, as he remarks, its young would have been smothered in a few 

 minutes after immersion. 



The Nototherium was about the size of an ox ; but the Dinotherium 

 was as big as the largest species of elephant. It certainly requires a 

 strong imagination to enable one to conceive the possibility of an 

 animal of such colossal dimensions, with two huge tusks hanging from 

 its lower jaw, carrying its young about in a pouch ! 



The Second Decade of Canadian Fossils, containing a Monograph 

 of the Graptolitidce, by Professor James Hall, is an important contri- 

 bution to the literature of that curious group of fossils, for in addition 

 to diagnoses of all the Canadian species, it contains a good description 

 of their general anatomy, and a discussion on their affinities. Not 

 long ago most palaeontologists thought the latter question was at 

 last settled in favour of the Bryozoa, so many high authorities hav- 

 ing given their support to that view ; and the discovery of a basal 

 plate in certain species seemed to provide the only wanting link, 

 namely, the presence, in some of the Graptolites of a structure known 

 to occur in Bryozoa and not in Hydrozoa. In the introductory chapter 

 to this decade, however, Professor James Hall, who is perhaps the 

 most celebrated of the American palaeontologists, describes external 

 organs of reproduction, consisting of ovarian vesicles, situated on the 

 stipe of the Graptolite, very much as similar organs occur on the stems 

 of recent Sertularidce. This is the second time, at least, that Professor 

 Hall has stated his conviction of the ovarian character of these sacs, 

 and if his opinion be well founded, the affinity of the Graptolitidos to 

 the Sertularians can no longer be contested. Professor Hall has satis- 

 fied hi m self that the " ovarian vesicles " were really attached to the 

 stipe, and originated from it ; he has also found young Graptolites of 

 extremely minute proportions, and in all stages of development, " near 

 to and in contact with the reproductive sac, and in one case there 

 is but a hair's breadth between one of the fibres of the sac and one 

 of the oblique processes at the base of the germ." The function of 

 this " reproductive sac, or ovarian vesicle," therefore appears pretty 

 certain, and consequently the Hydrozoan nature of Graptolites seems 

 equally so. 



One of the most paradoxical members of the series of sedimentary 



