592 IVAR TRÀGARDH 



dark-coloured tendons which attain a length of half the belly. 

 At the anterior margin of the subconical plate there is a pair 

 of straight, setiform hairs, surroiinded by narrow, depressed 

 areas. 



Behind the terminal plate, surrounding the anal aperture, 

 the edge of the body is an exceedingly thin, rounded blade which 

 projects beyond the posterior margin of the dorsal shield. 



This structure is uncertain of interprétation. From a compa- 

 rison with the nympha of Urodinychus Kramerii G. Can., in 

 which the anal aperture is bordered anteriorly by a small 

 shield, bearing a pair of small bristles, which I hâve interpreted 

 as an anal shield, between which and the anal aperture 

 there is a pair of small valvulae, while posteriorly it is borde- 

 red by a triangular plate, it seems probable that the basai plate 

 of Urosejus, into which the rest can be partly telescoped, is 

 homologuons with the anal shield of Urodinychus ; the 

 collar-shaped plate is the modified valvulae, and the post- 

 anal plate of Urodinychus is the terminal plate of Urosejus. 



The legs are well delineated by Berlese, and I hâve only to 

 add a more detailed desciption of tarsi I. 



Thèse hâve at the top small, horn-shaped projections, at the 

 dorsal side of which a long, straight bristle and a bundle of 

 sensillae and tactile hairs are placed (fig. 115). 



URODINYCHUS Berl. 

 U. Kramerii (G. Can) 



(Fig. 116-132). 



In a previous paper (1910, p. 457) I pointed out that 

 Berlese, in 1903, referred U. Kramerii, which has a single 

 dorsal shield, to the gen. Uropoda Latr., the type-species 

 of which, U. obscura Koch., has two shields, in spite of which 

 fact Berlese characterizes Urojjoda as « sciite dorsali intergo ». 

 I had, however, overlooked that in 1904 (p. 373) Berlese 



