CURRENT LITERATURE. gi 



Contributions to the Knowledge of the Mollusca. (Zeit. f. wiss. Zool., 

 liii, pp. 57S-590, 1S92, 1 pi.) 

 Herr J. Thiele opposes Pelseneer as to the nature and homologues of the 

 epipodium, which he regards as an organ of the lateral line, homologous with 

 that of the Polychceta. 



Anatomy of W. Indian Helices. (Proc. Acad. Nat. Sci. Philadelphia, 

 p. 128, 1892.) H. A. Pilsbry. 



Anatomy of some American Molluscs. (Proc. Acad. Nat. Sci. Phila- 

 delphia, p. 213, 1892). H. A. Pilsbry. 



Excretory Organs of Pulmonate Gasteropods. (Compt. rend, cxv, 

 p. 256, 1892.) L. Cuenot. 



Colourless Globulin in Patella. (Comp. rend. , p. 259, 1892). A. B. Griffiths. 



Histology of the Salivary Glands in Cephalopods. (Arch. f. Mikr. 

 Anat., xxxix, p. 596, 1892.) B. Rawitz. 



Note on a large Squid (Ommastrephes pteropus, Stp.). (Jour. Mar. 

 Biol. Ass., ii, pp. 314-321, 1892.) E. S. Goodrich. 



EMBRYOLOGY AND DEVELOPMENT. 



Development of Proneomenia. (Comp. rend., cxiv., p. 1211, 

 G. Pruvot. 



CLASSIFICATION AND NOMENCLATURE. 



Classification of the Nudibranchiate Gasteropoda. (Semper's Reisen im 

 Archipel der Philippinen (2), II., II, xviii, Wiesbaden, 1892, pp. 993-1165.) 



Prof. Bergh gives in this large quarto memoir a complete and revised classifi- 

 cation of the Nudibranchiate section of the Opisthobranchia, which latter, as is 

 well known, he divides into Uiree equivalent groups, the Tectibranchia, the 

 Ascoglossa, and the Nudibranchia. His earlier sub-division of the Nudibranchia 

 into the two sections, Kladohepatica and Holohepatica, is retained. No strict 

 grouping of the eleven families of the Kladohepatica is attempted, although they 

 include such different types as u-Eolis, Phylliroe, Pleurophyllidia, and Tntonia ; 

 but the fifteen families of the Holohepatica fall into four sections, the Dorididce 

 cryptobranchiatre, the Porostomata, the Dorididre phanerobranchiatre, ami the 

 Corambidas, and of these the Porostomata [Doriopsis, Phyllidia) are especially 

 connected with the D. cryptobranchiata;, and the Corambidae with the 

 D. phanerobranchiatoe. 



Bergh seems to regard the Nudibranchia as diphyletic, for he connects the 

 Kladohepatica with the Aplysiidce and Bullidae through the Ascoglossa (Oxynoe, 

 Stiliger, &c), and the Holohepatica with the Pleurobranchidoe. At the same 

 time he admits that in Trilonia we have a connecting link between the two great 

 sections of Nudibranchia, and expressly states that the time is not yet ripe for 

 determining the mutual relations between the different groups of Opisthobranchia. 

 There is even a touch of scorn in his references to " phylogenetic lucubrations." 



Very complete diagnoses are given (in Latin and German) of the organology of 

 the various groups and families, and the distinguishing generic characters are given 

 in Latin, together with complete lists of the known species and their distribution. 

 The memoir closes with a synopsis of the classification and an index. We are 

 ourselves inclined with Dr. Norman to believe that many of the generic distinctions, 

 for which Bergh is reponsible, will fail to stand the test of time ; nevertheless, we 

 think it incumbent to adopt them, as expressing the matured views of the most 

 experienced and careful investigator of the group. How far the progress of 

 investigation will confirm or modify these distinctions remains to be seen. 



The frequent recurrence of the phrase, "Concerning the biological relations of 

 these animals hardly anything is known," brings forcibly to our mind what 

 a great field there is for the most interesting of researches at our very doors. 



W G. 



