178 
ZOOLOGICAL LITERATURE. 
/ thiere. Brustflosse der Fische, Leipzig, 1865, 4to (pp. 
I 176, with nine plates). 
j [Humeral arch of Vertebrates. Pectoral fin of fishes.] 
Hollard, H. Recherches sur la structure de Fencephale des 
Poissons et sur la signification homologique de ses dif- 
I ferentes parties. Compt. Rend. 1865, April (pp. 768-770, 
j ' abstract). 
Langhans, Th. Untersuchungen fiber die Sclerotica der Fische. 
i Zeitschr. wiss. Zool. 1865, pp. 243-306, with two plates. 
j [Researches on the Sclerotica of fishes.] 
! Mayer — . Ueber die Chorda dorsalis bei den Fischen. Wiegm. 
Arch. 1865, pp. 342-344. 
I OwsJANNiKow, Ph. Ueber das Gehororgan von Petromyzon 
I fluviatilis. Mem. Ac. Sc. St. Petersb. viii. 1864, pp. 19, 
I with two plates. 
1 [On the organ of hearing of Petromyzon fluviatilis.'] 
^ Paulson, O. Die Epidermis von Protopterus annectens. Bull. 
! Ac. Sc. St. Petersb. 1865, viii. January (pp. 141-145, with 
j a plate) . 
i Robin, Cii. Memoirc sur les phenomenes et la direction dc la 
I decharge par Fappareil electrique des Raies. Ann. Sc. Nat. 
j 1865; iv, pp. 342-316. 
’ VoiT, C. Ueber die in den Schuppen und der Schwimmblase 
i von Fischen vorkommenden irisirenden Krystalle. Zeitschr. 
wiss. Zool. 1865, pp. 515-521. 
[On tlm iridescent crystals in the scales and air-bladder of 
. fishes,] 
V... 
Prof. Brandt has read before the Academy of Sciences of St. 
/ Petersburg a treatise on the classification of Cold-blooded Ver- 
/ tebrates, with particular regard to the question. What is a fish ? 
/ The treatise will appear in the Memoires of the Academy, but an 
I ' abstract is published in Bull. Ac. Sc. St. Pet. 1865, p. 535. The 
author, commencing from Aristotle, discusses the various ideas 
entertained by authors of a fish and the definitions given by 
those who regarded it as the type of a distinct class of the 
animal kingdom, and passes to the objections raised by Pallas 
and Owen against the separation of fishes as a distinct class. 
To prove that the reasons brought forward by these two authors 
are not of sufficient strength to unite the fishes with reptiles 
and amphibians, he gives the characteristics of warm- and cpltL 
