123 
MOLLUSCA. 
copulation both individuals are mutually fecundated. Etude 
anatomique et histologique sur Pappareil generateur du genre 
Helix, Paris : 1871, 56 pp. 1 pi. (abstr. in J. de Conch, xix. 
pp. 249& 250). 
There is another paper on the same subject by Joubdain, in 0. K. Ixxiii. 
Oct. 1871, p. 1059, abstracted in Ann. N. H. (4) viii. pp. 442 & 443. 
Sporleder has observed that Helix nemoralis and hortensis, 
after having lost their sagitta during copulation in May, develop 
a new one in the following September. Nachr. malak. Ges. hi. 
p. 17. 
Oysters in Sleswig contain during winter neither sperm nor 
ova ; in spring and summer some of them have been found with 
many ova, and others containing sperm, though none have been 
found to contain ova and sperm at the same time ; it is, how- 
ever, possible that the development of eggs may be followed by 
secretion of sperm in the same individual. Mobius, ibid, pp. 
131-134. 
Striated muscular fibres have been observed in a species of 
Acmcea by Ball ; Am. J. Sc. Febr. 1871, p. 123, and Am. Nat. 
iv. p. 691 . . They have already been observed by others in various 
genera. Q. J. Micr. Sci. (2) xi. p. 417. 
Haemoglobin is observed in the muscular fibres of the pharynx 
of Gastropods by Ray Lankaster : ibid, 
Manzoni recapitulates Semper’s observations on mollusks parasitic upon 
Ilolothuria and Synapta. J. de Conch, xviii. pp. 294-296. 
Ildix ericetoriim is observed to be active in December and January by 
Kobelt. Nachr. malak. Ges. iii. p. 78. 
Monstrosities, 
Sinistrnl abnormality of Bulirnus detritus : Dicrin, ibid, p. 188. Scalaroid 
abnormalities of Helix lapicida andiw?m<e« stagnalis, wadiFlanorhis complanatus 
\jnarginatus'] with disjointed whorls (ceratoid) ; Broeck, Ann. Mai. Belg. 
V. pp, 33, 37, pi. 1. figs. 1-3. A similar abnormality in Limncea limosa (L.) : 
Le Comte, ibid. p. ivii. Abnormal tentacles, the left being double, of Helix 
lapicida : Bboeck:, ibid. p. 24, pi. 1. fig. 4. 
GEOGRAPHICAL DISTRIBUTION. 
a. Land and Freshwater Mollusca. 
IIeynemann discusses the land-mollusks (especially the slugs) common to 
Europe and North America, in a manner somewhat too general. Nachr. 
malak. Ges. iii. pp. 90-92, 
Kobelt^s catalogue of European land and freshwater Mol- 
lusca enumerates 1591 species (including those of the Asiatic 
and African districts which belong to the same zoological pro- 
vince as Em^ope), and gives the habitat of each species and 
variety. The systematic arrangement of the Helicidce is similar 
