456 SUMMARY OF CURRENT RESEARCHES RELATING TO 



brachial, acetabulo-cutaneous, and inter-brachial) ; (3) of the con- 

 traction and dilatation of the suckers ; and (4) of the innervation. 

 His research deals with Octopus, Sepiola, Loligo, Sepia, and other forms. 



/3. Gastropoda. 



Snail on the Window-pane.*— M. Vies discusses the cause of the 

 noise sometimes made by a snail moving on the window-pane. He 

 thinks the sound, which is very definite and periodic, is due to the shell 

 rubbing against the glass. Another sound may be due to the radula 

 rasping on the glass. 



Movements of Gastropods.!— A. Robert discusses the movements 

 of progression in Haliotis, Helix, Chiton, Littorina, and other Gastro- 

 pods. He maintains that two modes of muscular undulation in the 

 foot, from in front backwards, or from behind forwards, may cause 

 progression, but the waves are not always equally distinct, and the 

 matter does not seem to admit of short formulation. 



New Prosobranch on Sea-urchins.} — R. Koehler and A. Vaney 

 describe three species of Pelseneeria g. n., which occur as ecto-parasites 

 on Echinus affinis and Genocidaris metadata, with their proboscis fixed 

 in the test. The new genus ranks with Mucronalia, Stylifer, and 

 Gasterosiphon as a group of Eulimidse. 



Abnormal Tentacles in Water-snails.§ — Albert Bauer has observed 

 numerous specimens of PlanorUs and Limnsea with abnormal tentacles. 

 Thus, the distal half in PlanorUs corneus may be thread-like and 

 tapering ; the tip in Limnsea staanedis may be slightly forked or 

 notched. These peculiarities are doubtless due to injuries. 



5. Liamellibranchiata. 



Geological Interest of Distribution of Fresh-water Mussels.|| 

 W. Kobelt points out in an interesting paper that a careful study of the 

 distribution of the species or sub-species of Unio in the Rhine and 

 related river-systems is certain to throw light on the former geological 

 relations. 



Arthropoda. 

 a. Insecta. 



Muscle Attachment in Insects.f — W. A. Riley is unable to accept 

 the view that the muscle-fibres are structurally prolongations of the 

 chitinogenous cells. The evidence very strongly supports Maziarski's 

 view that the so-called muscular fibrils passing through the hypodermal 

 cells are in reality modifications of its own protoplasm — true tono- 

 mitomes. 



* Bull. Soc. Zool. France, xxxiii. (1908) p. 145. 

 t Tom. cit., pp. 151-7 (2 figs.). 



X Bull. Inst. Oceanogr. Monaco, No. 118 (1908) 16 pp., 10 figs. 

 § Zool. Anzeig., xxxii. (1908) pp. 773-5 (4 figs.). 

 || Verh. Nat. Ver. Preuss. Rheinland, lxv. (1909) pp. 151-62 (1 pi.). 

 i Ann. Entomol. Soc. Amer., i. (1908) pp. 265-9 (1 pi. and 1 fig.). 



