2 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 82 



rounded in front and with three setae, the front two of which are 

 paired. Legs rather short; second pair stouter than the others. 

 Coxae II with a pair of spines; other coxae without spines. 



Type species. — Acanthocliela chilensis^ new species. 



Remarks. — Differs from Haemogamasus Berlese in having several 

 recurved, fanglike setae on the fixed arm of the chelicerae and from 

 Euhaemogamasus., described as new in this paper, in having many 

 setae on the sternal plate. 



ACANTHOCHELA CHILENSIS, new species 

 Plate 1, Figuke 1 



Body about twice as long as wide and well provided with short 

 setae. Palpi extending forward to tips of first patellae. Chelicerae 

 moderate, fixed chela of each somewhat swollen toward the apex 

 and bearing four recurved, thornlike setae. Sternal plate as broad 

 as long, front corners produced, acuminate, with two pairs of pore 

 slits and about 16 setae arranged more or less in pairs. Genito- 

 ventral plate over twice as long as broad, broadest between the last 

 pair of coxae, and ending in three lobes, the two lateral ones 

 acuminate and the central one rounded. Anal plate one and a half 

 times as long as broad ; anus situated less than its diameter from the 

 front margin; paired anal setae situated behind anus, single anal 

 seta much larger than paired ones and extending beyond tip of 

 anal plate. Legs of moderate length; second pair stoutest; third 

 pair smallest; only second coxae bearing spines. Length of female, 

 0.69 mm ; width, 0.39 mm. 



Type host. — Didelphis elegans. 



Type locality. — Lota, Chile. 



Type sZir/e.— U.S.N.M. no. 1066. 



Remarks. — Described from four females, collected by D. S. Bul- 

 lock, September 20, 1929, from type host, an opossum, at the type 

 locality. A very distinctive species. 



Genus HAEMOGAMASUS Berlese, 1889 



This genus, as restricted in this paper, may be described as fol- 

 lows: Body thickly beset with short, fine setae. Fixed arm of 

 chelicera not provided with recurved, fanglike setae. Ventral plates 

 of female as follows : Sternal plate usually large, provided with many 

 setae, some of which are not arranged in definite pairs ; genito ventral 

 plate not 3-lobed posteriorly ; anal plate longer than broad, broadly 

 rounded in front, and with three setae, the front two of wliich are 

 paired. Legs rather slender, second pair the stoutest. 



Type species. — Haemogamasus hirsutus Berlese, 1889. 



