president's address. 251 



Eiqjiecta, and tlie slug-like forms Africarion, Maricdlla, acd 

 Ratnadvipia, a new subgenus (cf. p. 253). The two first genera show 

 so many points in common, that they may be considered very closely 

 allied indeed. Enplecta presents certain affinities, yet it may be 

 noticed that in its dorsal lobes there is a departui-e from NUgiria. All 

 three have very small sessile spermathecas associated with a different 

 form of spermatophore. 



Ariophanta has its headquarters in this part of India, but ranges 

 northwards up to the edge of the Gangetic plain, only one species, 

 A. interrupta, crossing the delta and occurring in Jessore, seventy 

 miles north-east of Calcutta, although it has never been recorded 

 from further north, or east. As to A. retrorsa of Tenasserim and 

 Tavoy, I have always doubted whether it really belongs to this 

 group. I have, however, never had an adult example to dissect, 

 but the radula certainly presents considerable difi'erences. Several 

 Malayan species placed in this genus by Semper differ widely in 

 their anatomy, and must, I consider, be placed elsewhere. 



Euplecta is a genus typical of this Peninsula and presenting the 

 greatest development of species in Ceylon. In the details of its 

 generative system it shows a change, and one noticeable at once ; briefly 

 stated, a broad muscular band gathers a portion of the male organ 

 together and forms a loop. It possesses also a very small right shell 

 lobe, of about the same size as in M. pedina, but no left shell lobe. 

 The very striking form of the spermatophore, so very different from 

 any other with Avhich I am acquainted, is also noteworthy. Very many 

 species were originally placed in this genus of Semper's, yet I believe 

 myself that all foreign to this part of India will finally have to be 

 removed from it. The sculpture and character of the shell are very 

 marked. At present the only species still included in Euplecta that 

 await examination are two or three inhabiting Darjiling and the Khasi 

 Hills. These possess so very different a style of sculpture (of which 

 vidua may be taken as an example) that I cannot believe they are to be 

 associated with Euplecta. 



In southern India AJricarion^ represented by A. ater, stands alone; 

 no slug-like mollusc hitherto known on the Himalayan, or eastern side 

 can be placed near it. We have to go to East Africa to find one at all 

 similar in its anatomy ; it is another interesting example to add to the 

 list of species, pointed out by W. T. Blanford, as having a similar eastern 

 transoceanic connection. It was discovered by Colonel Beddome, 

 and I have not heard of anyone else who has been fortunate enough to 

 find it. Again, Maricdla is a genus of considerable interest. One 

 species, M. Beddomei, was described by me under the subgeneric title 

 I)e]chania. Gray founded his genus from external characters alone, 

 upon a single specimen in the British Museum, labelled Mahi, which 

 everyone had assumed to be one of the Seychelles Islands. Mr. 

 Cockeroll, however, was the first person to associate the name with 

 Mahe on the south-west coast of Peninsular India, and comparison of 

 the type with Beddome's specimens, and some others lately received 

 from Mr. Daly, of Mysore, confirms the identity. It has a very 

 remarkable similarity to Girasia of the Khasi Hills : there are 



