ANATOMY AND PHYSIOLOGY. 
Moll. 17 
Ou the development of the spermatozooids in Paludina vivipara ; M. 
Duval, Rev. Moutp. (2) i. pp. 211-231, 3 pis. 
Note on genital organs and copulation of Avion rufus, Lirnax cinereus, 
agrestis^ and gagates ; S. Jourdain, Rev. Montp. vii. pp. 411-423, with 
a pi. 
Description of the epithelium in the genital organs of Helix and 
Limax ; A. Butelli, Atti Soc. Tosc. (proc. verb.) ii. pp. 12 & 13. 
Preliminary note on the spermatophores of Helix from India ; H. 
Godwin-Austen, Rep. Brit. Assoc. 1879 (Sheffield), p. 377. 
An abstract of Pfeffer’s paper on spermatophores of Naninidm [Zool. 
Rec. XV. Moll. pp. 11 & 12), in J. R. Micr. Soc. ii. p. 304. 
The “ sagitta amatoria ” of Helix nemoralis is, according to the observa- 
tions of G. Arndt, reproduced within a week ; it is thrown out normally at 
the beginning of the copulation and acts as a stimulant on the genital 
organs of the partner. Arch. Ver. Mecklenb. xxxii. pp. 87-97. 
A. Kowalewsky gives some very interesting observations on the re- 
production and development of Chiton polii (Philippi), olivaceus, caietanus 
(Poli), and Acanthochcetes discrepans (Browne) ; the males eject the 
sperma into the seawater, the females their eggs on the outer skin above 
the gills, where they are fecundated ; in C. caietanus they remain agglu- 
tinated until the development of the larva. He further describes the 
cleaving of the yelk, the first formation of the gastrula, by invagination, 
the origin of the mesoderm from the endoderm, and its transformation 
to the free larva with a ciliated belt, and the appearance of the spicula 
and shell-plates, the former first occurring in the young state of all 
observed species. Zool. Anz. ii. pp. 469-473. 
10. Embryology. 
Ussow’s paper {supra) on the development of the Cephalopods has not 
been seen by the Recorder. 
The development of Planorhis marginatus and carinatus within the egg, 
with supplementary references to Limnceus, Physa, Ancylus, Succineay 
Helix hortensis, Paludina, and Bithynia, is the subject of an elaborate 
paper by C. Rabl ; after describing his own observations, he comes to the 
following general remarks on the development of the Mollusca. The 
ectoderm is always formed by the small clear-coloured cells of the yelk, 
the endoderm by the large dark-coloured cells. In the Pulmonata-Dermato- 
branchia, some Heteropoda, and Paludina, there is a true blastosphmra, 
the endodermal half of which is invaginated into the ectodermal (em- 
bolic) ; in the Pteropoda, Pleurohranchia, and most Prosohrancliia, the 
blastosphgera is very elongated and not really invaginate (epibolic). The 
development oiNatica is somewhat intermediate, these differences seeming 
to depend on the scarcity or abundance of the nutritive part of the yelk. 
The mesoderm originates from a few cells, situated where the ectoderm 
passes over into the endoderm, but more closely allied to the latter. The 
definitive mouth in all Mollusca is either directly the transformed orifice 
of the gastrula (archaeostome), or at least is situated exactly on the same 
spot ; the contradictory statements by Biitschli and Ray Lankester are 
