204 Bishopp — Some New North American Ixodidse. 



The engorged females are almost globular, the length and width differ- 

 ing but very little. In this respect this species is unlike other members 

 of this genus. 



The males may be distinguished from those of cookei by the basal spine 

 on coxae I being much shorter (less than one-half tbe length); the entire 

 tick smaller; sides of shield parallel ; absence of punctures on posterior 

 half of shield; presence of well-defined lateral carinae; shorter and 

 broader palpi; shorter, smaller legs; smaller stigmal plates; absence of 

 punctures on the ventral plates; width of anal frame in front of the anus 

 much greater. 



Nearly all of the other specimens at hand have rather shorter and more 

 slender legs and shorter basal spine on coxae I than the type and para- 

 types. The scutum, in a number of specimens, is somewhat smaller than 

 the type. The lateral carinae are distinct in all specimens. 



Ixodes angustus Neum. 



This species is abundant in various parts of the Northwest. The spec- 

 imens at hand show no decided variation, although some have the porose 

 areas less triangular and the scutum rather shorter and broader than 

 typical. It is worthy of note that out of thirteen lots of adults of this 

 species collected from hosts, only one contained male specimens. The 

 thirteen lots contained forty females and two males. Certain data relating 

 to specimens obtained by the Bureau in connection with the work con- 

 ducted on the Rocky Mountain spotted fever tick may be of interest on 

 account of their bearing on host relationship, distribution and seasonal 

 occurrence of the species. The material is contained in the collection of 

 the Bureau of Entomology at Dallas, Texas. During 1009 the following 

 collections were made: 2 9? 3 nymphs and 3 larvae from Ochotona princeps, 

 Meeteetse, Wyoming, July 7 ( W. V. King); 1 9 from Neotoma orolestes, 

 Casper, Wyoming, August 30 (M. Cary); 2 9 IromEutamias townsendi, 

 Detroit, Oregon, October :! ( V. Bailey) ; 6 9 and 3 nymphs from Sciurus 

 mollipilosus, Empire, Oregon, October 12 (V. Bailey); 14 9 irom Sciurus 

 mollipilosus, Empire, Oregon, October 1(>(D. D. Streeter). The follow- 

 ing collections were made during 1910: 2 9 from (Sciurus h. douglassi) 

 Mt. Lehman, B. C, March 12 (Dr. Seymour Hadwen); 3 9 and :'> 

 nymphs from (Sciurus h. douglassi) Silver Lake, Washington, April 7 

 (B. A. Bruce); 1 9 from Sciurus sp. Pysht, Washington, March 23 

 (Guy Decker); 2 9 from rabbit, Mora, Washington, June 13 (A. W. 

 Smith); 2 nymphs from Citellus columbianus, Florence, Montana, June 

 16 (W. V. King); 1 9 , 20 nymphs and 02 larvae from Ochotona princeps, 

 Florence, Montana, June 16 (W. V. King); 1 9 from Sciurus h. rich- 

 ardsoni, Lo Lo Hot Springs, Montana, June 23 (W. V. King); 2 9,7 

 nymphs and 2 larvae from Ochotona princeps, Lo Lo, Montana, June 29, 

 (W. V. King); 1 9 from cat, Pysht, Washington, July 6 (Guy Decker); 

 2 cT, 4 9 and 4 nymphs from rabbit, Pysht, Washington, August 30 

 (Guy Decker); 1 nymph from dog, Pysht, Washington, August 31 (Guy 

 Decker). 



