J. MURRAY ON GASTROTRICIIA. 221 



1909. B.festhians Yoigt. (69). 



1851. D. goniathrix Gosse (23). 



1909. D. ornatus Voigt. (69). 



1910. D. pa ucisetosus Marco. (40). 

 1887. D. saltitans Stokes (59). 



1901. D, stylifer Yoigt. (64). Is a Stylochaeta. 



1893. D. zelinkai Laut. (35). Seems to be D. goniathrix Gosse. 



1886. Ichthydium bogdanovii Schim. (51). Is a Chaetonotus. 



1905. /. crassum Dad. (14). 



1908. /. cyclocephalum Griin. (26). 



1882. /. entzii Dad. (11). Is a Chaetonotus. 



1901. I.forcipatum Voigt. (64). 



1861. I . jamaicense Schin. (52). Is a Chaetonotus. 



1897. /. macrurum Collin. (8). 



1865. /. ocellatum Met. (41). 



1861. /. tabulatum Schm. (52). Is a Chaetonotus. 



1908. /. tergestinum Griin. (26). 



1905. Gossea fasciculata Dad. (14). 



1905. G. pauciseta Dad. (14). 



1897. Lepidoderma biroi Dad. (12). Is probably C. entzii (Dad.). 



1905. L. elongatum Dad. (14). Is probably C. entzii (Dad.). 



1910. L. hystrix Dad. (15). Is probably C. entzii (Dad.). 



1890. Polyarthrafusiformis Spencer (56). Now genus Stylochaeta. 



1908. Setopus primus Griin. (26). Scarcely differs from Dasydytes. 



1776. Trichoda larus Mull. (43). Now Chaetonotus larus. 



Identification of Species. 



It was my ambition to accompany this paper by a key to all 

 the species hitherto described, so that the student might identify 

 them all, or at least know what characters they were supposed 

 to have. I found the task beyond my powers, for not only are 

 there a number of descriptions which I have been unable to 

 consult, but many of the diagnoses are such that to make use 

 of the characters given in them would be actually misleading. 



This is especially true of negative characters. Certain species 

 are described as having the body covered with scales, others as 

 having some or all of the bristles barbed or with supplementary 

 points. It must not be assumed that species not thus character- 

 ised do not possess those characters. Both are structures 



