136 
MOLLUSCA. 
Anatomy and Physiology. 
M. Foster & A. G. Dew Smith have published a paper “ On the 
behaviour of the hearts of Mollusks under the influence of electric cur- 
rents.” P. R. Soc. xxiii. pp. 318-343. 
A. Sabatier states that the gill-threads of the common mussel, 
Mytilua eduUa, are contractile like muscles. 0. R. Ixxxi. p. 1060, and 
R. Z. (3) iii. p. Ixviii. 
P. Fischer sketches the general disposition of the nervous ganglions 
in the terrestrial Pulmonata^ dividing them into three groups : supra- 
cesophagean, sub-oesophagean, and stomatogastric. C. R. Ixxxi. p. 782, 
and R. Z. (3) iii. p. lx. 
H. SiMROTH gives an anticipatory summary of a work on the organs 
of sense in the Mollusca^ chiefly of histological and morphological 
interest, but not capable of being extracted. Z. wiss. Zool. xxv. suppl. 
vol. pp. 244 & 245. 
J. Ranke has examined the otocysts of Pterotrachea in living and 
dead animals. He states that the apparently rhythmic movements of 
the cilia within the otocyst described by Boll are of convulsive nature 
and caused by pain in the animal ; in ordinary life, the cilia are not 
moved when the animal is quiet, but are erected on any rather loud 
noise being made. The auditory nerve does not reach these cilia, but 
terminates in very minute clear rods, called auditory bacilli (Hor-stabe) 
by the author. According to him, these are the sensitive organs, but on 
a louder noise being made, the otolith approaches the auditory rods by 
the agency of the cilia, and acts as a tetanometer and damper. Finally, 
the auditory organs of other Mollusca^ and especially those of the 
Cephalopods, are compared. Z. wiss. Zool. xxv. suppl. yol. pp. 77-102, 
pi. V. 
Two kinds of Spermatozoids, different in shape and size, found in 
Murex hrandaris (L.), are described by S. L. Schenk, SB. Ak. Wien, 
Ixx. pt. 1, pp. 434-439, 1 pi. 
A living specimen of Anodonta from Cochin China reached Paris, re- 
maining more than eight months enveloped in dry paper. Deshayes, J. 
de Conch, xxiii. pp. 81-84. 
Similar instances concerning Unio litoralis (Drap.), Spatha ruhens 
(Lam.), and an Australian species of Unio, the last surviving 231 days, 
are recorded by Gassies, Martin, and Gaskoin, tom. cit. pp. 194-196. 
Some remarks on the boring of several species by Macintosh, Ma- 
rine Invertebr. and Fishes of St. Andrews, pp. 69 & 60, and by W. D. 
Sutton, Q. J. Conch, i. pp. 49-50. 
Embryology. 
A popular account of the development of several genera of Mollusca, 
extracted from the works of Kolliker, Lacaze-Duthiers, Loven, Salen- 
sky, &c., is given by A. S. Packard, Am. Nat. ix. pp. 282-307, with 
numerous woodcuts. 
