en: N@oricus. 
VoL. XII. JUNE, 1898. No. 2, 
A LIST OF LAND AND FRESH WATER SHELLS OF ENGANIO WITH 
DESCRIPTIONS OF NEW SPECIES. 
BY JOHN B. HENDERSON, JR. 
The shells forming the subject of this paper were collected in the 
Island of Enganio by Mr. William Doherty, by whom they were 
sent to Mr. Aldrich, of Birmingham, Ala. Enganio, or Pulo Telan- 
jang, is a small island surrounded by deep sea, off the southwest 
coast of Sumatra, about one hundred miles west of Benkoelen. Mr. 
Doherty has published in the “Asiatic Journal” of Bengal, 1886, 
his observations upon this island. From geological features and 
the faunal relations of the birds and insects collected, he concludes 
that Enganio forms a continuation of a submerged mountain chain, 
isolated peaks of which constitute the present Nias group. He finds 
the fauna of Enganio to be more closely related to that of the Anda- 
mans and the Nicobars than to that of Sumatra, and also to possess 
decided Javan affinities. He finds other evidence of the long isola- 
tion of this island from either the mainland or neighboring islands. 
A study of these shells tends to confirm the correctness of his views. 
The land and fresh water mollusks of Perak, and, in general, of the 
entire Malay Peninsula, bear a striking resemblance to those of 
Enganio. I have been unable to learn anything about the mollus- 
can fauna of the Nias group, which, if known, would probably furn- 
ish additional evidence of the one-time closer connection of Java 
and the mainland through Enganio, the Nias group, the Nicobars 
and the Andamans. As will be seen, several of the species herein 
enumerated are identical with Javan forms, and others strongly 
