Bibliographical Notice. ^89 



figured, and which we are informed, in the above note, are male 

 and female of Cinosternou Peunsylvanicmn ; the " young female," 

 which I am accused of making a species, being in his own work 

 considered a distinct genus from the Cinostemon or Thyrosternon 

 Pennsylvnnicum ! 



If any one will take the trouble to compare the figures in the 

 two works, I think they will have little doubt that the synonyma 

 will stand thus : — 



\. Kinosternon Penmylvanictim, junior. Gray, Cat. t. 20 C. 

 f. 1, 2,=: Thyrosternon Pennsylvanicum, Agassiz, p. 428; 

 CinostcrnumPennsylvanicum,\)\. 4. f. 7 , 12, pi. 5. f. IG, 17. 



2. Kinosternon Hippocrepis, junior, Gray, Cat. t. 20 C. f. 3, 4, 



= Platythyra Jtavescens, Ag. p. 430 ; Cinosternnm fla- 

 vescens, Ag. pi. 5. f. 12, 15. 



3. Kinosternon punctatum, junior. Gray, Cat. t. 20 C. f. o, 6, 



= Thyrosternon Sonoriense, Ag. 428 ; Cinosternum Sono- 

 riense, Ag. pi. 5. f. 8, 11. 



I do not think it necessary to take any notice of the other 

 observations in this brief communication, but shall refer to them 

 in the Appendix to my Catalogue, which is in the press. 



BIBLIOGRAPHICAL NOTICE. 



Contributions to the Natural History of the United States of 

 America. By Louis Agassiz. Vols. I. and II. 4to. Boston : 

 Little, Brown & Co. London: Trilbner & Co. 1857. 



The first two volumes of .Vgassiz's ' Contributions to American 

 Zoology,' so long announced, and so anxiously expected by his friends 

 on both sides of the Atlantic, have at length made their appearance. 

 They contain, first, an essay on general classification, forming an 

 introduction to the whole work ; and secondly, the results of the 

 author's investigations on the Testuc/inata, to which he has devoted 

 much time and toil during the last few years. This is divided into two 

 parts, the first containing a special account of the North American 

 members of the group, and the second an extended and laborious 

 treatise on their embryology. The first portion of this book is of a 

 nature so generally interesting to all who take pleasure in studying 

 the laws and objects of creation, — it is so fairly and beautifully written, 

 and gives a view of the subject so much more complete and philo- 

 sophical than anything of the sort yet attempted, that it cannot but 

 be regretted that it should be obtainable only in conjunction with 

 the bulky work on a special subject, and which is, moreover, to be 

 Ann. ^ Mag. N. Hist. Ser. 3. Vol. i. 19 



