222 PROCEEDINGS OF THE NATIONAL MUSEUM vol. loi 



peritreme not clear. Epistome not figured or mentioned. Nearly all 

 setae on legs, except terminal setae on tarsi, are barbed. Distal mar- 

 gins of all leg segments, except tarsi, separated. 



Size. — ^Length of body 876/i ; width 560|ii. 



Disti'ihution and hosts. — The description was based on a single 

 female specimen found on Mus trivirgatus at Gonyon, Liberia, by 

 R. H. Bunting on November 20, 1910. Specimen in collection of 

 H. C. Rothschild. 



Remarks. — Distinguishing features of this mite are : Most setae on 

 dorsal and ventral surface barbed ; a large number of accessory sternal 

 setae present over entire shield ; two pairs of accessory setae on anterior 

 margin of sternal shield; six or seven anal setae; fixed chela with 

 bifid tip, two teeth, and a seta; movable chela with two teeth; most 

 setae on legs barbed. 



HAEMOGAMASUS AVISUGUS Vitzthum 



Haemogamasus avisugus Vitzthum, Zool. Jahrb. (Abt. Syst.), vol. 60, pp. 396-397, 

 1931. 



No specimens of this mite were available for study. The following 

 data are taken from Vitzthum's (1931) brief original description, 

 which did not include figures. 



Female. — Sternal shield with about 14 accessory setae. Usual 

 sternal and metasternal setae not distinguished in length and thick- 

 ness from accessory setae of sternal shield. Anterior pair of usual 

 sternal setae strongly barbed; the others smooth. Genito ventral 

 shield at its broadest part broader than the distance between coxae 

 IV. Chelicerae of female with toothlike, sharply bent tips. Fixed 

 chela with two teeth; movable chela with one tooth. Dorsal and 

 ventral body setae smooth except along posterior body margin. Most 

 setae on legs barbed. 



Male. — Fixed chela of male normally formed with one tooth and 

 a normal pilus dentilus. Proximal half of movable chela very thick ; 

 its distal half strongly bent, and deeply split, with a sperm carrier 

 which reaches far beyond its end. Anterior margin of each coxa finely 

 serrated. 



Remarks. — Because of the unusually brief description and lack of 

 figures it is difficult to determine the relationship of this mite to others 

 in the genus. However, the fact that the sternal shield of the female 

 possesses only about 14 accessory setae and that these are as large 

 as the usual setae is distinctive. No other member of the genus pos- 

 sesses only one tooth on the movable chela. Vitzthum's description 

 of the chelae of the male most closely fits H. mandschuricus. 



Size.—L&wgth. of female 925/^ to 960/x ; length of male 775/a to 800/*. 



Distribution and host. — On Ri'paria riparia in Germany. 



