76 



In the female the head is less than twice as long as high (seen from side); the first 

 genal spine in the head comb is only about one-half the length of the second; in 

 the male the manubrium of clasper is very distinctly enlarged at tip; but one 

 row of hairs on the disc of the movable finger C. canis Curtis. 



NeopsyUa. — One species of this genus has been described from the 

 brown rat ia Europe. 

 NeopsyUa bidentatiformis Wagner. 



The eyes are very small; there are 4 pairs of lateral spines 

 beneath the last joint of the hind tarsus; the comb on head consists 

 of but 2 stout spines, below the middle of the antennae; the pro- 

 notal comb has 18 spines; the proportions of the joints in the hind 

 tarsus are 43-33-21-12-21. 



Length: Male, 2 to 2.3 millimeters; female, 2.3 to 2.5 millimeters. 



Not yet found in the United States ; described from Russia. 



SARCOPSYLLID^. 



The fleas of this family are commonly called "chigoes," "jiggers," 

 or sand fleas. The head is usually larger proportionally than in the 

 other fleas; there are no ctenidia on head or pronotum; the thoracic 

 segments are extremely short, and in the female the abdomen enlarges 

 with the development of the eggs. They do not hop about as other 

 fleas, but remain on the spot to which they have attached until they 

 die. Frequently the adjacent skin grows over them, forming a 

 swelling of considerable size. 



Three species belonging to two genera have been recorded from rats. 



1. Angle of head acutely produced; fifth tarsal joint of hind legs without heavy spines; 



few spines on the legs Sarcopsylla. 



Angle of head not produced, obtuse; fifth tarsal joint with heavy lateral spines, 

 and other spines on other parts of the legs Echidnophaga. 



EchidnopTmga. — Two species of this genus are laiown from rats; 

 one, however {E. gallinacea), can hardly be called a normal parasite, 

 but rather of accidental occurrence. The genus has also been called 

 ArgiopsyUa and Xestopsylla. 



1. Bristles at end of second joint of hind tarsus about as long as next three joints; 



palpi about one-half the length of mandibles E. rhynchopsylla. 



Bristles at end of second joint of hind tarsus about as long as next two joints; 

 palpi about two-thirds the length of the mandibles E. gallinacea. 



Echidnophaga rhynchopsylla Tiraboschi. 



The body is about twice as long as broad and shining brown; there 

 is but one hair in front of eye, and four on each metathoracic pleuron; 

 mandibles larger than in E. gallinacea, and the spiracles are much 

 higher up on the sides than in that species. Length, 1.4 to 1.8 milli- 

 meters. 



Taken from Mus rattus in Italy. 



