6 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 82 



CYCLOLAELAPS CIRCULARIS, new species 



Plate 2, Figures 2-4 



Body almost circular but observed to be slightly pointed in front 

 and behind and sparsely clothed with rather short, spinelike setae, 

 which are more consjDicuous near the margin. Chelicerae with 

 rather small chelae; movable chela much stouter than fixed one and 

 surpassing the latter, with three teeth exclusive of the terminal 

 process; fixed chela slightly curved, with two teeth exclusive of the 

 terminal process, cheliceral seta absent. Sternal plate about twice 

 as broad as long, front margin convex, posterior margin concave, 

 the sternal setae subequal, curved, and forming two divergent rows. 

 Genitoventral plate almost twice as long as broad, the single pair of 

 setae extending to apex. Anal plate subtriangular, anal opening 

 situated in front of center of same, paired anal setae shorter than 

 unpaired one and situated on a level with posterior margin of anal 

 opening. Metapodal plates oval, in diameter equal to that of anus. 

 Legs stout; last pair longest; coxae I, II, and IV each with a single 

 spinelike seta; coxae III each with two spinelike setae. Length of 

 female, 0.65 mm; width, 0.55 mm. 



Tyye host. — Perotnyscus truei truei. 



Type locality. — Salina, Utah. 



Type 6•^^V/es.— U.S.N.M. no. 1071. 



Remarks. — Described from two females taken from type host, the 

 large-eared deer mouse, collected at the tj^pe locality by J. S. Stan- 

 ford, one on November 22, 1928, and one on December 7, 1928. 



Genus MACROLAELAPS Ewing, 1929 



Body stout, but longer than broad, not subcircular; well clothed 

 with short, spinelike setae; dorsal plate of female sculptured. Cheli- 

 cerae each with a brush of setae attached near the base of the 

 movable arm; fixed arm without recurved, fanglike setae. Sternal 

 plate of female broad, with two pairs of pores and three pairs of 

 setae; genitoventral plate not reaching anal plate; anal plate about 

 as broad as long, broadly rounded in front and pointed behind, and 

 provided with two paired and one unpaired setae. Legs stout, pro- 

 vided with spinelike setae; each coxa with one or two short, peglike 

 spines. 



Type species. — Laelaps sanguineus Vitzthum. 



Remarks. — Species of this genus are the largest of any belonging 

 to the subfamily Laelaptinae. The genus is related to Geneiadolae- 

 laps Ewing, but differs from it in having the body sculptured above 

 and the legs and body clothed with stout, spinelike setae. 



