1891.] GEOGRAPHICAL DISTRIBUTION OF SLUGS. 225 



Indian region \ Mariaella, a very distinct genus, has almost 

 identical forms in S. India, Ceylon, and the Seychelles. Parmacoehlea 

 has a single species from the northern extremity of Queensland, 

 but is represented in the Indian region by a subgenus Pseudaustenia 

 (nov. nom.) of Ihi/cus, the type of which is the Africarion ater of 

 Godwin-Austen. Austenia is a genus of the Indian region, with some 

 very different species, which will probably form new subgenera. 



Helicarion is very numerous in species, about 101 being known. 

 The genus is quoted from Africa, the Indian, Chinese, and Malay 

 regions, Australia, &c. It is very noteworthy, however, that it seems 

 to be absent in New Zealand, the H. dimidiatus of that island being 

 an Otoconcha. It is found, nevertheless, in the Auckland Is. {H. 

 zebra, Le Guill.), Lord Howe's I. {U. hitli. Cox), and New Caledonia 

 (jS. keppelli, Pfr.). It is best developed in Australia (18 species) 

 and the Philippines (17 species). When the animals are fully 

 known, the genus will doubtless have to be subdivided. Such species 

 as n. cumingii. Beck, and H. bocki. Smith, might be separated from 

 Helicarion by their shells alone, at least subgeuerically. 



n. vitrinina and H. ramsayi of Liardet, from the Fiji Is., probably 

 represent a single species showing colour-variation of the animal. 



Testacellid^. 



Testacella and Daudebardia are genera belonging to the European, 

 or, more precisely. Western Palaearctic, region, each with a fair 

 number of species. These genera have also been reported from New 

 Zealand, but probably the species referred to by Hutton (Trans. 

 N. Z. Inst. 1883) belong to some other genus. Chlatnydephorus is 

 a distinct and peculiar genus from South Africa, with one species. 

 Selenochlcimys, Bitg., founded on a species from Transcaucasia, is 

 allied to Daudebardia, but has no shell. 



SelenitiDwE. — Trigonochlamince. 



A family allied to Testacellidce, but possessing a jaw. The present 

 subfamily includes Triyonochlaviys and Pseudomilax from the Cau- 

 casian region, and Plutonia from the Azores, the latter mouotypic". 



Cystopeltince^. 

 Contains only the remarkable genus Cystopelta of Tate, founded 

 on a single species, C. petterdi, found in Tasmania. 



1 The group of G. crocea, G.-A., althougli true Girasia, shows a resemblance 

 to Mariaella in some of its t-haracters. The species which I described as Girasia 

 depressa I now consider to be a variety or subspecies of G. crocea. 



2 A most important work hy Dr. Simroth on the Portuguese, Azores, and 

 other Slugs has just appeared '(2sova Act. Acad. Cces. Leop.-C'ar. 1891), con- 

 taining a detailed account of 'Plutonia. 



3 Mr. Hedley has lately published a very interesting paper on Cystopelta in 

 Proc. Linn. Soe. N. S. W. 1890, p. 44. It would seem that this subfamily is 

 intermediate between Selenitidce and HelicarionincB. 



Proc. Zool. Soc— 1891, No. XV. 15 



