NO. 1301. REVISION OF AMERICAN SiPIIONAPf ERA— BAKER. 397 



lower fourth. On the middle of hind margin of antennal groove 

 occur a few minute hairs, while just back of the margin on disk of 

 vertex stands one stout bristle. The usual bristles occur on hind 

 margin of head, with a large long one at lower angle on either side. 

 Labial palpi about equaling anterior coxai. The fourth joint of maxil- 

 lary palpi is unusually slender. 



Fronotum with a transverse row of twelve l)ristl('s and on liiiid 

 margin a ctenidium of eighteen stout spines. Hind margin of meta- 

 notum with two small teeth on each side, first and second abdominal 

 tergites the same, the third' with onl}" one on each side. Abdominal 

 tergites with two rows of bristles each, the larger bristles, eighteen 

 in number on each of the middle segments. Middle abdominal ster- 

 nites with three or four bristles on each sid<\ Antepygidial bristles 

 three on each side, the middle one of each group very large, the other 

 two small, though not reduced to hairs. Hind margin of lateral por- 

 tions of eighth segment with about six stout bristles. Lateral i)ortion 

 of ninth tergite with a short, thick lobe, which is o))liquely truncate 

 and bears a hair at tip. The upper clasper is short and thick, almost 

 crescentiform, with the hind margin rounded and the upper end acutely 

 angled, but the base is broad; on the upper portion of the hind margin 

 there are two bristles and two or three hairs. 



Hind coxa without minute teeth inside. Hind fenujr with a row of 

 four or five distant bristles on the side. Apical spines on second joint 

 of hind tarsi shorter than third joint; first pair of spines on last joint 

 distinctly dislocated toward median line. Length of middle tarsal 

 joints in the proportion 12-12-9-5-12. 



Length, 2.5 mm. Color, pale brown; middle of dorsum darker. 



JVi>6.— Cat. No. 6905, U.S.N.M. ' 



CERATOPHYLLUS CILIATUS, new species. 

 Plate XVI, figs. 1-6. 



Mr. Ehrhorn also contributes from Mountain View, California, the 

 male luid female of a species occurring on a chipnumk. It is closol}' 

 related to callformcus. Unfortunately the male of the latter is 

 unknown, l)ut the females differ in many characters. 



F(Mnale: Head rather strongly rounded from occiput to mouth, the 

 minute frontal notch rather low down. Lower row of genal l)ristles of 

 three sul)C(|ual bristles, the upper row of four or five much smaller. 

 Eyes ovate and low down in head. Antennal groove rather small and 

 reaching two-thirds the depth of the head. Bristles on second antennal 

 joint much shorter than third joint. Hind margin of antennal groove 

 with a few minute hairs, especially near the lower angle. Caudad of the 

 middle of the antennal groove, on the disc of the vertex, are three 

 bristles, two small and one large one, the latter situated almost on the 

 margin of the o-roove. Hind niaruiu of the head with the usual bris- 



