AET. 15 



NEW NEMATODE FROM THE RAT — CRAM 



female (28 mm. lonf^ by 500[j(, wide). The second white rat died on 

 January 23; upon postmortem examination 2 specimens of P. col- 

 umhianu, mature but not fully ^^rown adults, were found in the 

 stomach, one male (24 mm. long by HOOu. wide) and one female (30 

 mm. long by 850[ji, wide). 



On December 27 encysted larvae, obtained by dissection of one of 

 the remaining roaches, were fed to white rates and mice. On April 

 21, 2 of the rats and 1 mouse were killed. From the stomach of one 

 rat were recovered 8 specimens of P. columhiana (7 females and 1 

 male), from that of the second rat 7 specimens (3 females and 4 

 males), and from that of the mouse 1 specimen (male). These 

 nematodes had attained the size of those found originally in the 

 wild rats, the females measuring up to 88 mm. long by 2.2 mm. wide, 

 the males up to 43 mm. long by 1 mm. wide. 



A tabulated summary of the above feeding experiments is as 

 follows : 



KNOWN SPECIES OF PROTOSPHIDKA 



The species of the genus Protospimra may be distinguished Jis follows: 

 1. Each lol)e of lips with 1 large tooth and 2 smaller teeth ; 6 cephalic i)apillae ; 



eggs 16m long by 7^ wide P. laModentata. 



Lobes of lips with teeth of different number than above ; 4 cephalic papillae ; 

 eggs, wiiere known, much larger than IGfi by 7m 2. 



