598 



IVAR TRAGArDH 



of the hysterosoma etc. It is therefore in many instances almost impossible 

 to know to which genera to refer many species and this applies especially to 

 the United States, where a great number of species are rather imperfectly de- 

 scribed. The present species is a good instance of this deplorable state 

 of knowledge. On the wohle it seems to be most closely related to the 

 genus Chamobates Hull characterized by Hull as follows: »Small species. 

 Lamellae small. Translamellae absent. Tridactyle. Type species: cuspidatus 

 MlCH.» 



To this genus Hull (p. 393) refers two species with distinct cusps on the 

 lamellae and four species without distinct cusps or angles on the lamellae. 

 Nevertheless Sellnick (1929, p. 14) writes ou Chamobates'. »Lamellen endigen 

 in eine scharfe Spitze; das Lamellenhaar steht am Grunde der Spitze auf dem 

 Propodosoma.» 



If, however, we accept the views of Hull, which 

 we ought to do, there is nothing that prevents us 

 from referring the present species to Chamobates, at 

 least provisionally. 



Length 730 [i. Width 510 (x. 

 Colour light brown; texture polished. 

 Propodosoma very short, measuring only about 

 one fifth of the entire length. The demarcation line 

 between the propodosoma and hysterosoma is curved 

 in an even curve forwards and very distinct on dis- 

 sected specimens but otherwise rather difficult to dis- 

 cern. The rostrum has a short, rounded, median 

 mucro set off from the lateral margin by two short, 

 rounded incisions. Rostral hairs straight, a little more 

 than half as long as the lamellar hairs. The lamellae 

 are about half as long as the propodosoma and of 

 almost even width throughout, with slightly wavy 

 dorsal margin and tapering rather abruptly towards 

 there is no cusp. No translamellae. Lamellar hairs 

 a little behind the point, where the dorsal edge of the lamella dis- 

 appears, straight and as long as the lamella. Interlamellar hairs straight, by 

 ^/2 loriger than the lamellar hairs. Behind the insertion points of the lamellar 

 hairs, there are a couple of dark, rounded spots, close to the anterior margin 

 of the hysterosoma (fig. 92). 



Pseudostigmata funnel-shaped (fig. 93), with a distinct constriction in 

 the middle, which divides them into a larger external and a narrower interior 

 part. They are situated at the sides of the propodosoma and almost completely 

 hidden by the anterior edge of the hysterosoma which in front oft hem seems 

 to be coalesced with the lamellae. Seen from above the external margin of 

 the pseudostigma has a sharp, tooth-shaped projection pointing obliquely back- 

 vi^ards and outwards. On lateral view the exterior part of the margin projects 

 a little more beyond the edge of the pteromorpha than the median one. 



Pseudostigmatic organ (fig. 96) with long, slender peduncle, curved 



Fig. 91. 



Chamobates margine- 

 dentata n. sp. 



the anterior end, where 

 inserted 



