269 
ON A NEW GENUS AND SPECIES OF SIPHONAPTERA 
FROM NYASALAND. 
By tHE Hon. N. CHaries RoruscuHiyp, M.A., F.L.S., F.E.S. 
The Entomological Research Committee has received from Zomba four 
specimens of a new species of flea which is related to the genera Leptopsylla, 
Roths. (1911; type museuli, Duges, 1832) and Palaeopsylla, Wagn. (1902 ; 
type minor, Dale, 1878 = gracilis, Tasch., 1880) but differs so much from the 
species belonging to these genera that it requires a separate genus. The 
species is especially remarkable for the development of its head and buccal 
organs (fig. 1). The mandibles as well as the labrum are very broad, particu- 
larly the former, and closely resemble those of Spilopsyllus cuniculi, Dale (1878), 
and the SarcopsYLLIDAE. This peculiar parallelism also obtains in the labial 
palpi, which show a reduction similar to that which occurs in the fleas mentioned, 
being but feebly chitinized and consisting of only three distinct segments. The 
size of the Jabrum and mandibles suggests that the species fixes itself to the 
host by means of these organs in the same way as Spilopsyllus cuniculi, 1.e., 
more permanently than do the majority of fleas. The structure of the head 
bears out this surmise inasmuch as the buccal slit extends far upwards, the 
frons being short, which allows the piercing organs to assume an almost 
horizontal position when being driven into the skin of the host. 
The new genus, which we propose to call Chimaeropsylla, gen. nov., is further 
characterised by the first segment of the mid tarsus being one-fourth shorter 
than the second, and the first of the hind tarsus as long as the second segment. 
Fig. 1—Head of Chimacropsylla potis &. 
