THE NAUTILUS. 



Vor,. XXVII. JANUARY, 1914. No. 9 



LIST OF LAND SHELLS FROM SWAN ISLAND, WITH DESCRIPTIONS OF 



FIVE NEW SPECIES. 



BY W. F. CLAP I'. 



The following list is based on the land shells found on Swan 

 Island by Mr. George Nelson in April 1913. The material was 

 collected for the Museum of Comparative Zoology, Cambridge, 

 Massachusetts. 



Swan Island is situated in the Caribbean Sea about one hundred 

 miles northeast of Spanish Honduras, and three hundred and fifty 

 miles west of Jamaica. About one quarter of the land is cleared 

 and devoted to the raising of cocoanuts ; the remaining three-quarters 

 is an almost impenetrable jungle. The soil, rich in lime and phos- 

 phate, and the luxurious vegetation, render the island an ideal home 

 for the land mollusca. 



From the standpoint of the zoogeographer the fauna of the island 

 is of considerable interest. With so few species represented, it is 

 impossible to be positive when and whence it obtained its molluscan 

 fauna; but further collecting should yield a greater number of species, 

 from which interesting conclusions may be drawn, regarding former 

 land connections in this region. 



The Chondropoma is most closely related to Cuban or Haitian 

 species; the Braclypodella to Cuban, although its resemblance to 

 B. costulata of Jamaica is striking. The Csecilioides is also Cuban. 

 The Lucidetta and Drymaus are both closely allied to both Jamaican 



