258 : Mr. E. E. Austen on 
Speiser follows Rondani in relying on the coloration of the 
hair on the clypeus and apex of the abdomen, and he uses 
these characters to distinguish what he now calls H. drome- 
darina from what he regards as the true H. camelina, Leach ; 
but he also considers that the two supposed species may be 
distinguished by the colour of the thorax, the paler form 
being H. camelina, the darker H. dromedarina, Speiser. It 
is curious that Speiser should come to the conclusion, from 
the examination of Leach’s original description and figure, 
that camelina was based on the pale form, since a glance at 
the coloured figure (in the Museum copy of Leach’s paper, 
at any rate) is sufficient to show that it represents the dark 
and not the pale form. A still better argument, however, is 
supplied by the type itself, which is in the Museum collection 
and bears a label in Leach’s handwriting. This specimen (a 
female, as indicated by Leach’s figure) belongs to the dark 
form, but has pale hair on the clypeus and abdomen. Accord- 
ing to Speiser, the true H. camelina, Leach, is pale brown in 
eolour, with pale hair on clypeus and apex of abdomen ; 
while what he calls H. dromedarina is dark blackish brown, 
with black hair on the clypeus, and on the abdomen black 
hairs mingled with the pale ones. A series of specimens in 
the Museum collection, from Algeria (Rev. A. HL. Eaton), 
with one exception agree with the type in belonging essen- 
tially to the dark form, although the hair on clypeus and 
abdomen is pale. The specimen which constitutes the excep- 
tion also has the ground-colour of the thorax dark, but the 
clypeus is fringed with black instead of with pale hair, and 
the apex of the abdomen is clothed with hair which is black 
at the base instead of entirely pale; it may be added that 
this specimen was bred and is accompanied by its puparium. 
In two females from Shaik Othman, near Aden, Arabia, 4. iii. 
1895 (Lieut.-Col. Yerbury), which belong to the dark form, 
the hair fringing the clypeus is certainly dark brown at the 
base, but that on the abdomen is as light-coloured as in the 
pale form ; on the other hand, in a. male from Arabia (J. K. 
Lord) belonging to the dark form the hair on clypeus as well 
as abdomen is entirely pale. It is to be hoped that enough 
has now been said to show that we are here dealing with but 
a single species, which is variable as regards the ground- 
colour of the thorax, and sometimes as regards the colour of 
the hair on the clypeus and abdomen, and that Hippobosca 
dromedarina, Speiser, like H. bactriana, Rond., must be con- 
sidered a synonym of H. camelina, Leach. 
The Museum collection includes a series of some thirty- 
three specimens of EH. camelina, Leach, from various localities 
