10 PROCEEDINGS OP THE NATIONAL MUSEUM Vol.68 



Thoracic spiracles medium, situated dorso-laterally. Abdomen with 

 well marked segmentation; all the larger setae arranged in trans- 

 verse rows. Pleural plates well chitinized and almost black; pleural 

 plate I (fig. 4,A) small, almost circular, scarcely twice the diameter 

 of the spiracular bulb it contains; pleural plate II squarish, not 

 lobed; pleural plate III smaller than IV but with very distinct 

 lateral lobes; pleural plate IV with large and conspicuous lateral 

 lobes but not so long as V; pleural plate V the longest of all the 

 plates but only slightly lobed laterally; pleural plates VI and VII 

 without lateral lobes. Legs moderate ; femur III almost twice as long 

 as broad, tibia III about two and a half times as long as broad. 



Length, 2.15 mm. ; width, 0.80 mm. 



Type host and type locality. — Ateles geoffroyi (gray form, or 

 TnelanochiT type of coloration) ; type locality?. 



Type.— C^t. No. 28105, U.S.N.M. 



This species differs from the others particularly in the characters 

 given in the preceding key. Described from a male specimen taken 

 from the skin of Ateles geoffroyi (U.S.N.M. 155393). This Ateles 

 skin is from one of several specimens kept some years ago at the 

 National Zoological Park. Three of the skins are marked almost 

 exactly alike (grey type, w^ith black on head, hands, feet, elbows, 

 and Imees). The writer has noted infested living specimens of 

 Ateles geoffroyi in the National Zoological Park, but has never had 

 the opportunity of examining any of their lice. 



In addition to the male specimen mentioned the w^riter has ob- 

 tained nits from skins of Ateles geoffroyi as follows: From skin 

 (U.S.N.M. 12150), taken at Talamanca, Costa Kica, by W. M. Gabb; 

 from skin (U.S.N.M. 12151) taken at the same place by the same 

 collector; from skin (U.S.N.M. 01209) taken in Costa Rica and from 

 skin (U.S.N.M. 154223) (locality and collector ?). 



PEDICULUS (PARAPEDICULUS) CONSOBRINUS Piaget 



Plate 1, figs. 1 aud 2 ; text figs. 2 aud 3D 



1880 Pedicnlus consohrinus Tiaget, Les Pediculiues, p. G2G, pi. 51, fig. 4. 

 1908 Pcdlculus consohrinus Dalla Torre, Gen. Ins., Anop., p. 8. 



1910 Pcdiculus affinis Mjoberg, Ark. f. Zool., vol. 6, no. 13, p. IGO, fig. 85. 



1911 Pcdiculus consohrinus Neumann, Arch. Par., vol. 14, p. 412. 

 1913 Pcdiculus consohrinus Faiirenholz, Zool. Anz., vol. 41, p. 372. 



191G Pcdiculus mjijhcrgi Feruis, Proc. Cal. Acad. Sci., ser. 4, vol. 6, p. 136. 

 1919 Pcdiculus humanus Nuttall (in part). Parasitology, vol. 11, p. 334. 



Female. — Head rather short; neck scarcely differentiated and 

 poorly chitinized, the ocular plates stopping abruptly and bearing 

 a low tubercle at their posterior margins; forehead short, about twice 

 as broad as long. Antennae about equal to the head in length; 



