( 364 ) 



Mid-tarsns : c? 10, IS, 11, 0, IT ; ? 24, 21, 12, 9, 18. 

 Hind-tarsus : S 48, 30, 17, 10, 18 ; ? 51, 33, 18, 11, 19. 



Modifed Segments. — S. The eighth tergite has an irregular row of small 

 bristles from tlie lower end of the stigma upwards. The widened apical portion of 

 this segment has four or five bristles at the upper edge and four to six on the side. 

 The clasper (PI. VII. fig. 3) has a straight manubrium fM) with the apex rounded. 

 The proeess (P) of the clasper is broad and sliort. The two bristU's placed near the 

 insertion of the finger (F) are thinner than the largest bristles of the eighth tergite. 

 The movable process F greatly widens from the base upwards, being broadest 

 beyond the centre. Its proximal edge is almost straight, apart from a central angle, 

 while the distal margin is strongly convex beyond the centre. The oblique ujijier 

 portion of the distal margin is notched in the middle and bears a moderately large 

 bristle between this notch and the upper proximal angle. Besides this bristle there 

 are only a few very slender ones and some minute hairs on the finger. Tlie ninth 

 steniite (PI. YII. fig. 3, ix. st.) is of the type found in C./a.iria/i/s and allies. The 

 proximal lobe of the exopodite of this segment bears two short strong spiniform 

 bristles. 



?. The seventh steniite varies in outline to a considerable extent, but its 

 apical margin is always evenly incurved, as shown in tlie figure (PI. VII. fig. 5); the 

 upper angle is either pointed or more or less rounded oft', and sometimes hardly 

 projects as a lobe. The eighth tergite has numerous small bristles above the stigma, 

 and two to four long ones below it accompanied by one or two small ones. On the 

 widened ventral portion of this tergite there are eight bristles along the ventral and 

 apical edge on the outer surface, six or seven long lateral ones, and seven to fifteen 

 small lateral bristles placed proximally to the long ones. 

 A series of both sexes was obtained, as follows : 

 17 cJcJ, 20 ? ?, from Khenchela, oS Meiiom's s/imri, May 1912. 

 2 (JcJ, 4 ? ?, from Gnelt-es-Stel, o'S Ja cuius or/e>italiK, April 1912. 

 One of the Khenchela ? ? is a very interesting aberration, inasmuch as it 

 throws light on the jihylogenetic development of the bristles of the fifth tarsal 

 segment. In the genus Ceratophi/llus this segment bears five pairs of ventral lateral 

 bristles, of which the first pair is frequently placed on the ventral surface and 

 sometimes even in between the second pair of bristles. Some genera not very dis- 

 tantly related to Ceratophi/llus were originally chiefly separated from one another 

 on account of the development of the plantar bristles. Seoj)Si/!/a, for instance, was 

 based by Wagner mainly on the fifth hind-tarsal segment bearing only four pairs of 

 lateral bristles. The presence, absence, and position of the first pair of these bristles 

 are therefore considered to be of important taxonomic value. Now, in the specimen 

 of C. mattrus referred to above, all the tarsi have only four pairs of plantar bristles, 

 as in yeopHi/Ua, with the exception of one mid-tarsus which has retained one bristle 

 of the proximal pair lost in the other tarsi. 



7. Ceratophyllus henleyi mauretanicus subsp. nov. (PI. VIII. fig. 7 and 9). 



S ? . The specimens from Southern Algeria dilTer slightly, though ]ierce])tibly, 

 from those which we have from Egypt, and which are C. lu-nUiji he.nleiji Roths. 

 (1904). The eighth tergite of the S of C. h. henleiji bears six bristles along the 

 upper margin and eight or more on the side. In C. h. mauretanicus (PI. VIII. fig. 7) 

 there are four bristles and a hair at the margin, and four to six at the sides, of which 



