Mr. E. A. Smith 07i Arctic MoUusca. 131 



and ventral, constructed much as in Necroscia Salmanazar^ 

 N, maculicollisj and N. sparaxes^ in all three of which also the 

 sixth ventral segment is furnished at its hinder extremity with 

 a peculiarly shaped process, which serves as the jJoint d^appiii 

 for the claspers of the male during copulation. Legs long 

 and stout ; the fore tibise and the femora and the tibiee of the 

 two posterior pairs subtriquetrous and carinate along the 

 middle of the under surface. Tegmina oval, with but a slight 

 compressed conical elevation of the carina. Wings reaching 

 about to the end of the fifth abdominal segment ; the costal 

 area luteous brown, like the body and legs ; the costal vein 

 divided at the middle of its length, the two branches uniting 

 again near the extremity ; posterior area milk-white, conspi- 

 cously tessellated with dark smoky-quartz-colour, all the trans- 

 verse veinlets being broadly and distinctly margined on each 

 side with this colour. 



Total length 3 inches 7 lines ; head 3*25 lines, prothorax 

 2*5, mesothorax 7"25; abdomen 1 inch 8 lines -|- 4 = 2 inches; 

 antenna? 2 inches 5 lines ; wings 1 inch 10 lines ; tegmina 

 5*5 lines ; fore femur 12" 75 lines, tibia 14*5, tarsus 6*75 ; inter- 

 mediate femur 8*5 lines, tibia 9*5, tarsus 5 ; posterior femur 

 13*5 lines, tibia 14, tarsus 5" 75. 



Hab. Southern slopes of the Khasi hills. 



Closely allied to N. Salmanazar^ Westw. (Monogr. Phasm. 

 p. 153, pi. xvi. fig. 6), ? , from the Philippines. 



Calcutta, June 26, 1877. 



XX. — On the MoUusca collected during the Arctic Expedition 

 o/" 1875-76. By Edgak A. Smith, Zoological Department, 

 British Museum. 



The chief interest attaching to the MoUusca obtained during 

 the Arctic Expedition arises from the collections being made at 

 localities further north than any wliicli had been previously 

 investigated. 



It is somewhat disappointing, considering that unexplored 

 regions were searched, that only a single new form was pro- 

 cured. 



The entire collection consists of thirty-four species. This 

 may appear a very small number ; but the difficulty experi- 

 enced in collecting in such northern climates in a great mea- 

 sure accounts for such small results. It by no means proves 

 that there is any great scarcity of molluscan life in the regions 

 investigated. In all probability, further research will discover 



9* 



