222 



A NATVBALIST IN CELEBES 



In the lake itself, however, there are found in great 

 numhers a small fresh-water prawn, which I have named 

 after the Jkhr van der Wyck, Eesident of Manado, Atya 

 Wyckii (38). This species differs very considerably from 

 other species of the genus Atya, and some carcinologists 

 have expressed an opinion that it should be separated 

 from them in another genus. 



The species of fresh-water prawns which are collected 

 together in the genus Atya have a very wide geographical 

 distribution, being found in Mexico, West Indian Islands, 



Fig. 32. — Atya Wyckii, a small prawn found in Lake Tondano. 



2. The same, natural size. 



Cape Verde Islands, the Moluccas, Philippines, Samoa, 

 Tahiti, and elsewhere, A curious feature of their distri- 

 bution is that they are but rarely found in continental 

 rivers and lakes. The cause, whatever it may be, which 

 confines them to the fresh water of the islands has not yet 

 come to light. Our information is at present unfortu- 

 nately not very exact as to the localities inhabited by 

 these curious forms. Atya sulcatipes is said to live at a 

 height of 300 feet above the sea-level at San Nicalao, in 



