552 SUMMARY OF CURRENT RESEARCHES RELATING TO 



Hydrachnid Fauna of Scotland.*— W. Williamson gives a list of 

 all the recorded Hydrachnidae for Scotland. It would appear that these 

 are mainly confined to the neighbourhoods of Oban, Edinburgh, Glasgow, 

 and West Kilbride, so that this fauna does not seem to have been much 

 worked. Fifty-four species in all are known, and of these fourteen are 

 now recorded for the first time for Scotland. 



New Pycnogonid from the Bahamas.f — Leon J. Cole describes 

 Barana latipes sp. n., the only Pycnogonid obtained during an expedi- 

 tion to the Bahamas. The genus Barana Dohrn is undoubtedly very 

 close to Parazetes Slater, and the two should perhaps be united. 



e. Crustacea. 



Regeneration of Lost Parts in Lobster.f — Victor E. Emmel finds 

 that antennules, antennae, inaxillipedes, chelipeds, walking legs, first 

 abdominal appendages, swimmerets, telson, beak, etc., may be re-grown 

 when injured. 



The thoracic appendages have a varying power of regeneration at 

 different levels, but most at the " breaking-plane " between the second 

 aud third basal segments. As this is the region at which the limbs when 

 injured are almost always " autotomously " severed, the comparative 

 perfection of re-growth at this region may be the result of selection. 

 Begenerated chelipeds of young lobsters attained a normal size at the 

 third moult. Repeated removal of the right cheliped showed in each 

 successive regeneration a larger percentage of difference between the 

 lengths of the regenerated and the normal limbs. There is an adapta- 

 tion of both regenerative and moulting processes to the regenerating 

 limb, favourable to the development of a functional appendage at the 

 first moult after injury. 



Larvae of Macrura Eucyphota.§ — H. Coutiere describes the curious 

 larval forms of Caricyphus, Diaphoropus, Hectarthropus, Icotopus, and 

 Thalassocaris. It seems that very diverse species have a prolonged 

 mode of development, characterised by a uniform larval phase, much 

 elongated, adapted to pelagic life, inherited from Schizopod ancestors, 

 and doubtless terminating in an abrupt genital crisis, with probable 

 reduction of size. 



Antarctic Isopods.|| — Harriet Richardson discusses the Isopods 

 collected by the French Antarctic Expedition. The collection is marked 

 by the multiplicity of special forms, and by the gigantic dimensions of 

 some of them. Two new genera — Antias and Austrimunna — are 

 established. 



Male of Nicothoa astaci and the Suctorial Apparatus. ^| — A. Quidor 

 has studied the insufficiently known male of this parasite of the crayfish. 

 In the early immature stages the two sexes are indistinguishable, except 



* Trans. Edinburgh Field Nat. and Micr. Soc, 1905-6, pp. 1-3. 

 t Amer. Nat., xl. (1906) pp. 217-22 (2 pis.). 



% Twenty-rifth Report Inland Fisheries Rhode Island (Providence, 1905) pp. 

 81-117 (2 pis.). 



§ Comptes Rendus, cxlii. (1906) pp. 847-9. 



tl Tom. cit., pp. 849-51. f Tom. cit., pp. 465-8 (2 rigs.). 



