PALEONTOLOGY. 295 



for the coiisiderablo variation of the Grastero[)0(l in its " general form, 

 contiguration ol'the aperture, and tlie surface markings." In spite of 

 the clear recognition of tliis plasticity of form the antiior has been nna- 

 ble to resist the temptation to name and define in terms of these plastic 

 characters the four new species above mentioned. 



THE CEPHALOPODA. 



Alpheus Hyatt (121) has presented a valuable paper, strictly biological, 

 in which he discusses the value of embryological characters in the defini- 

 tion and classification of the Cephalopoda, lie proposes a new nomen- 

 clature for the stages of development of the embryo, and applies the 

 classification in distinguishing the various stages represented by the 

 fossil Cephalo[)oda. In a brief review it is impossible to give the sub- 

 stance of this paper, and those interested are referred to the article 

 itself, which is fully as interesting as the im{)ortant works on similar 

 sul)jects whicli Professor Hyatt has already published. Professor Hyatt 

 also read a paper before the National Academy, at the Boston meeting, 

 on the [)rimitive forms of Gephaloj^ods (119), an abstract of which is 

 given in the American Naturalist, as above cited. It is difiQcult to ex- 

 l)ress in briefer words the contents of this valuable paper. The author 

 discusses the phylogenetic relations of the Paheozoic and later Cepha- 

 lopods, particularly in respect to their characters of curving, from the 

 straight coiled form, as seen in Orthoceras, to the close coiled Nautilian 

 form. 



In the report of Contributions to Canadian Palaiontology, by Pro- 

 fessor Whiteaves (29.!), two generic descri^itions are communicated by 

 Professor Hyatt (120) from theTriassic rocks of British Columbia. The 

 names are — 



Arniotifes, Hyatt, gen. uov., p. 144, type Balatonifes arietiformis, Mojsisovics. 

 DorikTaniles, Hyatt, gen. uov., p. 145, type BaJaiointc>i nagdoaniis, Mojsisovics. 



Arthur H. Foord (86) publishes a note on the genus Actinocerm with 

 particular reference to specimens in the British Museum showing the 

 perforated apex of the Siphuncle; the specimens illustrated are from 

 the Trenton and Black River rocks of the United States, British North 

 America, and Arctic America. The same author (87) writes on the 

 genus Piloceras Salter, as elucidated by examples lately discovered in 

 North America and Scotland. The bibliography of the genus is re- 

 ferred to, the internal stru(;ture is described and illustrated, and the 

 characters discussed, based upon study of Scotch and American speci- 

 mens. 



ARTIIROPODA. 



A. S, Packard published in 1887 several memoirs which were read 

 before the National Academy of Sciences in 18S5, and their contents 

 have already been reported in the scientific; Journals. 



The first (218a) "On the Syn<;arida, a hitherto nnde.scribed synthetic 

 groupof extinct Malacostracous Crustacea''^ {vol. iir, pp. 123-128, and two 



