66 
The Non-Combed Eyed Siphonaptera 
cesses, the smaller one bearing one long apical bristle and some shorter 
ones. The manubrium is slightly club-shaped. The ninth sternite is 
canoe-shaped in side-view, narrowing rather strongly basally.— $. The 
eighth tergite has, on the outside, 3 long lateral bristles and a subapical 
row of 5 to 7, there being 4 to 6 short apical bristles on the inside. 
Length. £ T4 mm., $ 2 2 mm. 
We have a small series of both sexes from Cairo, Egypt, off A cornys 
caldrinus and Jaculus jaculus 1 , taken in January and March, 1901, by 
N. C. Rothschild and A. F. R. Wollaston. 
We also received a pair of cotypes of alternans Wahlgr. from the 
Riksmuseum at Stockholm. 
5. Genus: Rhopalopsyllus Baker (1905). 
Rhopalopsyllus Baker (1905a, p. 128, type of name: lutzi; descript, erroneous); 
Rothschild (1906, p. 173). 
The short description which Baker gave of his genus Rhopalopsyllus 
is erroneous and insufficient. From the incidental statement, however, 
on page 130 of the treatise quoted above that “ the upper edge of the 
antennal groove usually has a row of many short and thick, but minute, 
spines or teeth,” we may safely conclude that the name Rhopalopsyllus 
was meant to apply as a generic term to the species characterised 
below. 
Head. Frons always with notch (PI. II, fig. 3). Antennal groove 
extended to the vertex in both sexes, widely open behind, the genal 
process being short (Ph II, fig. 3). First segment of the antennae long 
in </ and $ ; second almost square in side-view, bearing several bristles at 
the hinder edge, the last bristle being the longest and stoutest; club 
a little longer in than in 5. segmented all round, the segments 
deeply separated on hinder side, the first elongate-ovate, the next 
three lamelliform in lateral aspect, separate, very oblique in position, 
inclining apicad (PI. II, fig. 3). In both sexes a row of short, stout, 
spine-like hairs along the antennal groove, standing close together, the 
row extending from the hinder edge of the head to the central row of 
bristles of the occiput. Occiput with at least one row of bristles besides 
the subapical row. Labial palpus consisting of 5 to 7 segments; the 
segmentation very distinct all round; tip of last segment excised, 
bearing 3 small hairs on each side (PI. II, fig. 9). There are 3 bristles 
1 The specimen of Jaculus jaculus from which a L. chephrenis was taken had been kept 
in captivity for two days in a cage with a live Acomys cahirinus. This flea is probably 
confined to A. cahirinus. 
