Siphonaptera from Asiatic Russia. 543 



The modified abdominal segments of the ? do not present 

 any reliable difference from the allied species, the outline 

 and bristles of the eighth tergite being individually variable. 



A series of both sexes from near Djarkent, Semitchenskoi, 

 East Turkestan, October 15th and November 15th, 1912, off 

 Meriones tamaricinus. 



5. Ceratophyllus ?'epandus, sp. n. (PI. XV. figs. 6, 9.) 



c? ? . — The frons has in both sexes a distinct tubercle. 

 The bristles of the head and legs are similar to those of 

 C, teretifrons, but the anterior row of the frons contains one 

 or two bristles less. 



The clasper resembles that of teretifrons, but the finger is 

 a little shorter and bears fewer bristles at the posterior 

 margin, the interspace between the longest bristle and the 

 next below it being wider than in teretifrons. The widened 

 central portion of the ventral arm of the ninth sternite 

 (fig. 6) is more gradually dilated, and the bristles it bears 

 are much less prolonged. There are in this place four 

 bristles, the first being the shortest and thinnest and the 

 other gradually increasing in length. The ventral angle of 

 the dilated apex of this segment is rounded, and not trian- 

 gular as in the two preceding species, and the apical hook of 

 the penis is much broader, shorter, and more obtuse than in 

 curvispinus and teretifrons. 



The seventh and eighth abdominal segments of the ? 

 (fig. 9) are apparently indistinguishable from those of 

 teretifrons. The stylet, however, is half as long again in 

 teretifrons as in repandus, being in teretifrons as long as the 

 fourth hind-tarsal segment. 



A series of both sexes from near Djarkent, Semitchenskoi, 

 East Turkestan, October 5th, 1912, off Meriones tamaricinus. 



6. Ceratophyllus consors, sp. n. (PI. XV. figs. 7, 8.) 



cJ ? . — A near ally of C. henleyi, Roths. (1904), and 

 maurus, Jord. & Roths. (1912), the apical bristles of the 

 hind-tarsal segments being long and the dorsal ones of the 

 meso- and metanota and proximal abdominal tergites 

 forming in the <$ a kind of mane. Two of the apical 

 bristles of the second segment of the hind tarsus extend con- 

 siderably beyond the apex of the fourth segment, being some- 

 what longer than in henleyi and maurus. C. consors, however, 

 is more easily differentiated by the modified abdominal 

 segments. 



In the d the eighth abdominal tergite (PI. XV. fig. 7, 



