46 MISC. PUBLICATION 5 0, U. S. DEPT. OF AGRICULTURE 



Thrassis desertorum' Stewart 



Thrassis desertorum Stewart, 1937, Canad. Ent. 69 : 273, tigs. 1 and 2. 



Type host. — Ammospe? v mophilus leucurus (Merr.) (antelope 

 squirrel). 



Type locality. — Eiverside County, Calif. 



Range. — Known only from California. 



A comparison of a male par a type of Thrassis desertorum with the 

 male holotype of T. arizonensis shows that the two species are very 

 close to each other. Probably a further study of a large series of 

 specimens of each species will indicate the reduction of desertorum to 

 a subspecies or variety of T. arizonensis. 



Thrassis fotus (Jordan) 



Ceratophyllus fotus Jordan, 1925, Navitates Zool. 32; 107, fig. 30. 

 Ceratophyllus citelli Stewart, 1928, Canad. Ent. 60: 150, figs. 3 and 4. 

 Thrassis fotus Jordan, 1933, Novitates Zool. 39 : 73. 



Type host. — Citellus tridecemlineatus (Mitch.) (13-striped ground 

 squirrel). 



Type locality. — Colorado Springs, Colo. 



Range. — Western part of the United States. 



The original description of this species is accompanied by a figure 

 of the clasper of the male and sternal plate VIII of the same sex. 



Thrassis francisi (C. Fox) 



Ceratophyllus francisi C. Fox. 1927, Amer. Ent. Soc. Trans. 53 : 210. 

 Thrassis francisi Jordan, 1933, Novitates Zool. 39 : 73. 



Type host. — Citellus mollis (Kenn.) (ground squirrel). 



Type locality. — Utah. 



Range. — Known only from Utah. 



In this species each spine of the pair situated on the proximal 

 lobe of the posterior process of sternal plate IX of the male is greatly 

 flattened and bladelike, with an exceedingly long and finely pointed 

 apex. Wagner (83, p. 343) in 1935 redescribed this species, illustrat- 

 ino- the terminali a of the two sexes. 



i & 



Thrassis gladiolis gladiolis (Jordan) 



Ceratophyllus gladiolis Jordan, 1925, Novitates Zool. 32 : 108, figs. 32 and 33. 

 Thrassis gladiolis Jordan, Novitates Zool. 39: 73. 



Type host. — ^Citellus turdicaudatus^ (ground squirrel). 



Type locality. — San Diego, Calif. 



Range. — Known only from California. 



The original description of gladiolis is accompanied by a drawing 

 of the clasper of the male and the posterior process of the sternal 

 plate IX of the same sex. 



Thrassis gladiolis caducus (Jordan) 



Ceratophyllus gladiolis caducus Jordan, 1930, Novitates Zool. 35 : 268-269, fig. 2. 



Type host. — Ammospermophilus lew\curus (Merr.) (antelope 

 squirrel) . 



