624 SUMMARY OF CURRENT RESEARCHES RELATING TO 
Tunicata. 
Different Forms of Anchinia.* — Prof. A. Korotneff describes an 
asexual form of Ancliinia , which differs in its mode of budding from the 
other two asexual forms previously described. Including the sexual 
generation there is thus a polymorphism of four stages. 
INVERTEBRATA. 
Mollusca. 
y. Gastropoda. 
“ Nebenkern ” in Spermatogenesis of Pulmonata.f — Mr. J. A. Murray 
has studied the history of this body in Helix pomatia and in Avion. 
The most important result of his research is the conclusion that in the 
attraction-sphere ( Nebenkern ) of Pulmonata there are no structures 
which can in any way be compared to chromosomes. “ The salient 
characters by which these are recognised — constant number, equal dis- 
tribution to the daughter-cells, and longitudinal division — are absent.” 
This conclusion is strongly against the supposed high importance of 
the constituent elements of the attraction-sphere as such. 
New South African Marine Gastropod. J — Mr. G. B. Sowerby de- 
scribes a remarkable mollusc, which has characters in common with the 
Volutidae, Buccinidae, and Fusidae. The soft parts, which have been 
described by Mr. M. F. Woodward, have some resemblance to those of 
the Volutidae, and are quite unlike those of Fusidae and Buccinidae. 
The most striking feature in the shell is its apex ; the nucleus being 
large, and of a bulb-like form ; otherwise it would be taken for a species 
of Neptunea Bolton = Chrysodomus Swainson. Mr. Sowerby proposes 
Neptuneopsis Gilchristi g. et sp. n., as the name of this new Gastropod. 
Caudal Triangular Groove of Arion.§— M. Emile Andre describes 
this in A. empiricorum Fer. and A. fuscus Miill. It is a depression 
bounded anteriorly by the mantle, and laterally by the margins of the 
sole. It is lined by epithelial cells among which there are calcareous 
and mucous unicellular glands. The secretion is greatest at the time 
of reproduction in spring. It may be odoriferous, and Saint-Simon has 
noted that two slugs eat one another’s mucus before pairing. It has no 
toxic quality. 
5. Ijamellibranchiata. 
Australasian Shipworms.j| — Mr. C. Hedley describes Calobates fluvi- 
atilis sp. n., from a river in Fiji, and compares it with other forms. The 
soft parts rather than the hard parts should be taken as a guide in 
classification. A salient character is the cup-like process of the mantle 
which embraces both siphons and palettes ; the siphons differ in the 
extent to which they are divided. The genus Calobates Gould is re- 
modelled, and is characterised by a cup-like anterior fold of the mantle 
and short siphons divergent for half their length. It thus embraces 
* MT. Zool. Stat. Neapel, xiii. (1898) pp. 426-32 (1 pi.). 
t Zool. Jahrb. (Abth. Anat.). xi. (1898) pp. 427-40 (2 pis.). 
% ‘ Report of the Marine Biologist (Cape of Good Hope) for the Year 1897,’ 
issued 1898, pp. 132-4. § Rev. Suisse Zool., v. (1898) pp. 179-82 (1 fig.). 
|| Proc. Linn. Soc. N.S.W., xxiii. (1898) pp. 91-6 (9 figs.). 
