8 Moll . 
MOLLUSCA. 
Concerning the conchological journals : — vol. xxv. of the French 
“ Journal de Conchyliologie,” 418 pp., 13 pis. ; vol. xxiv. of the German 
“ Malakozoologische Blatter,” 185 pp., 3 pis. ; vol. iv. of the German 
“ Jahrbuch der deutschen Malakozoologischen Gesellschaft,” 368 pp., 
12 pis., and “ Nachrichtsblatt ” of the same, 96 pp. ; Nos. 10-13 of the 
English “ Quarterly Journal of Conchology,” pp. 101-288, 3 pis. ; vol. iii. 
pts. 1-3 of the “ Bullettino della Societa Malacologica Italiana,” 48 pp., 
1 pi. ; and vol. iv. of the Italian “ Biblioteca Malacologica” (see Strobel), 
were published in 1877, and have been seen by the Recorder. Some 
older parts of the Italian “ Bull, della Societa mal. Ital.,” and of its pre- 
decessor, the “ Bull, malacologico Italiano,” are included in this Record. 
Anatomy and Physiology. 
R. Gauner gives some general remarks on the structure of the 
Mollusca, and their place in the animal kingdom, maintaining the affinity 
with the BracMopoda and Tunicata. Ann. N. H. (4) xix. py). 356-380. 
S. Trinchese, “ Struttura del sistema nervoso dei Molluschi Gastero- 
podi,” Pisa ; 1871, 8vo, 78 pp., 5 pis., treating chiefly on the microscopical 
structure of the ganglions and peripheral nerves of Helix pomatia ; and 
L. Stieda, “Notizie preliminari nell’ in tima struttura del sistema nervoso 
della Sepia oj/icinalis,'^^ Rend. Acc. Nap. x. [Dec. 1871], may be mentioned 
here as omitted before. 
H. V. IiiERiNG has published a larger work on the nervous system 
and phytogeny of the Molliisca (title see above), the chief results of 
which, as to the classification, have been anticipated by his preliminary 
note of the preceding year [see Zool. Rec. xiii. Moll. pp. 14 & 15]. He 
insists on the fundamental differences between his PlatycocTilides [Opis- 
thobranchia and Pulmonata, hermaphrodite Gastropods] and Arthrococh- 
lides '[Prosohranchia, unisexual Gastropods], the nervous system in the 
lowest forms of the latter very much resembling that of the Turhellaria, 
whereas in the loAvest Arthrococldides it has transversal commissures, 
which give the appearance of a ladder of ropes (Strickleiter). 
The strict symmetrical arrangement of the single organs in pairs of 
equal size and structure is, according to the author, the lower or more 
original, and the asymmetrical arrangement prevailing on one side, rudi- 
mentary development on the one and translation from one to the other, 
the higher or more differentiated type in the Mollusca. He endeavours 
to point this out in the gills, nervous systems, &c. 
C. Semper states that, in Vaginulus, and (somewhat modified) even in 
Limax^ the ladder-hke connection of the nervous trunk exists, contradic- 
tory to Ihering’s classification ; Arb. Inst. Wurzb. iii. pp. 480-488. H. 
V. Ihering denies the value of this statement ; SB. Soc. Erlang, ix. 
pp. 131-168. 
H. V. Ihering has published further anatomical researches upon the 
nervous system of Chiton, Fissurella, Scalaria, Turritella, and Vermetue. 
The last two are very near each other, as are Scalaria and Janthina 
[which confirms the importance of the radula for classification]. Morph- 
JB. iii. pp. 155-178, pi. x. 
