1884.] OF THE 'CHALLENGER' EXPEDITION. '2~>9 



possible, and very few references have been made to books, and 

 little or no synonymy given, as in most instances the species are 

 well known, and there is no likelihood of such as are mentioned 

 being misunderstood without reference to descriptions aud figures. 



Japan. 



Only a single pulmonate mollusk was brought from this country, 

 namely Philomycus bilineatus of Benson, found at Yokohama. 

 This species was originally described from specimens collected by 

 Dr. Cantor at Chusan, and has also been recorded from Amur, and 

 in the Britisli Museum tbere are two specimens from the island of 

 Formosa. The striping of the mantle appears to vary. Benson's 

 example had a median stripe along the back and one on each side, 

 just as in one of the two specimens from Chusan in the British 

 Museum, the other having only the two laterals, the central part of 

 the back being spotted and dotted with black, but not distinctly 

 lined. The Formosan Slugs previously referred to have five stripes, 

 two on each side and a central one. The ' Challenger ' specimen 

 has only a single lateral broad band on each side, the middle of the 

 dorsal surface being black-dotted but not definitely striped. 



Malay or Eastern Archipelago. 



Twenty-two species of land and freshwater shells (none of them 

 new forms) were collected at the Philippines, Moluccas, Ke, and 

 Aru Islands. They are as follows : — 



1. Nanina citrina, Linn. 



Hab. Amboyna, and Ke Dulan, Ke Islands. 



Six specimens of immature growth were collected at the former 

 locality, representing three varieties of this polymorphous species. 

 All are thin and have a silky upper surface, with the exception of 

 the apex, which is glossy, as is the case with the lower surface. 

 One example is uniformly pale greenish yellow, with an opaque yel- 

 low peripheral zone and a narrow infrasutural band of the same tint. 

 Two others are similarly ornameuted, but in addition have a rich 

 hrown zone above the opaque yellow one at the periphery. The re- 

 maining three examples are pinkish brown above, and pale, semi- 

 transparent, and faintly yellow below, encircled at the middle by the 

 usual whitish band, which is margined above with a zone of some- 

 what darker hue than the general tint of the upper surface, into 

 which it insensibly blends. There is also a white narrow line 

 beneath, but at the suture. 



The five shells from Ke Dulan, a locality hitherto I believe un- 

 assigned to this species, are remarkable for their solidity, one of 

 them also being unusually conical in the spire. They are glossy, 

 lacking the silky appearance obtaining in the Amboyna examples, 

 which may be present perhaps only in younger specimens. They 

 are lemon-yellow and differently banded. Two have a broad opaque 



