Bibliographical Notices. 11 



The descriptions of the five classes of Vertebrata occupy twenty 

 chapters ; but, from the fragmentary condition in which their 

 remains frequently occur, a more general account of each class is 

 given, with definitions of the orders and a brief notice of the 

 leading forms of each, except in cases of special interest, which are 

 more fully described. 



Under the class of Pishes the author notices the bodies called 

 " Conodonts " from the older Palaeozoic rocks, and which have been 

 variously referred to Mollusca, Crustacea, and Fishes. The latter 

 affinity, as originally suggested by Pander, is supported by Prof. 

 Newberry, who is inclined to the view that they are really the 

 minute teeth of Cyclostomatous fishes allied to the living Lampreys 

 and Hag fishes. A similar opinion is held by Mr. Hinde (in a paper 

 to the Geological Society), from the examination of a large number 

 of specimens from the Cambro-Silurian and Devonian rocks of 

 Canada and the United States, who considers, notwithstanding the 

 differences in minute structure, we should not reject altogether 

 the probability that they may have belonged to a similar low type 

 of fishes as the existing Myxinoids. 



The elevation of the Platysomoid fishes to the " rank of a distinct 

 division of the Ganoids," as given at p. 138 on the authority of 

 Dr. Traquair, does not coincide with the views of that author, as no 

 such proposition occurs in the unpublished paper referred to by Dr. 

 Nicholson in the footnote of the same page. On the contrary, Dr. 

 Traquair (in a letter to the 'Annals,' Dec. 1879) holds "that the 

 Platysomidae, as a family, are not really allied to the Pycnodontidae, 

 but are, on the other hand, so closely linked to the Palaeoniscidae 

 by ties of structure, that wherever we place the latter family, 

 thither the Platysomidae must follow." 



The remarkable forms of Vertebrata lately described by Professors 

 Cope and Marsh from the rich fossiliferous localities of the Western 

 Territories, and which have so largely enriched the museums of 

 Newhaven and Philadelphia, are noticed. Of these the most 

 important are the Sauranodontia, Pteranodontia, and Dinosauria 

 among Reptiles, the Tillodontia, Dinocerata, and Brontotheridae of 

 the Mammals, and the Odontornithes among the Birds — which 

 latter group will probably receive further elucidation from the 

 forthcoming memoir of Prof. Marsh. 



The third part, containing four chapters, is devoted to Paleo- 

 botany ; but scarcely any thing more is attempted than to give a 

 brief and elementary sketch of the general distribution of plants in 

 time, to which is added a short summary of the chief forms of vege- 

 table life which more particularly characterize each of the great 

 formations. The subject instead of being botanically is geologically 

 treated ; so that only the main features of the successive floras from 

 the Pre-carboniferous to the Tertiary are noticed. But little new 

 matter has been added to this part ; so that the account of the Car- 

 boniferous, Permian, Triassic, Jurassic, and Eocene plants remains 

 nearly the same as in the former edition. 



The Avork is well printed ; the 722 woodcuts, with a few excep- 



