REVIEWS. 
73 
three, is subject to this exception, that Henops has only two. The posi¬ 
tion assigned to the family seems questionable, after what Erichson has 
demonstrated of the structure of the oral organs. He has proposed for it 
a place after the Syrphidce and preceding the Myopidce , Conopidce , and 
Oestridce : much might be said in favour of this view, but more perhaps 
against it. 
5. AsiLiDiE.—This family, as to the contents of which there can be no 
dispute, is well characterized. The proboscis, however, is not very happily 
described in general, as u very sharp.” The veining of the wings ought 
to have been regarded, and the empodium, which is not developed like a 
pulvillus, but crowned by a single stout bristle. The phrase, repeated 
under every genus, “ ocelli on a tubercle,” belongs to the family character, 
not to that of any genus, being common to them all alike. The abdomen 
of the Asilidce does not (as it is here stated) consist of seven segments, 
but of eight. The eighth segment in the males is ordinarily very minute, 
sometimes unsymmetrical, and for the most part nearly concealed. In the 
females it is more apparent; in those of the genus Asilus it is mostly mo¬ 
dified in shape, and forms part of the compressed two-jointed ovipositor. 
When this consists of more than two joints, one or more of the preceding 
segments partake of this alteration, as, for instance, in the subg. Itamus. 
6. Leptidjs. —This family is very insufficiently characterized. Not a 
word is said of the peculiar veining of the wings, of the shortness of the 
epistoma, or of its peculiar form; nor yet of the presence of two-jointed palpi, 
of terminal spurs to the tibiae, or of the development of the empodium in the 
nature of a pulvillus. On the other hand, the antennae are termed “ setiformes,’’ 
meaning “ in setam terminatae this is inapplicable to the genus Spania , 
which is here rightly referred to the family Leptidce. The segments of the 
abdomen are reckoned as seven : there are eight of them in reality. The 
eighth, indeed, may easily be overlooked, on account of its small size and 
retracted position in the male. 
7. Bombylid^e _This family is made to include the genus Thereua , or, 
according to the antiquated mode of spelling, which Mr. Walker has retained, 
Tliereva . His inducements to this coalition have probably been the hairy 
body of most of the Thereuce , and the palpi composed of a single joint. 
We cannot but consider it as a very unnatural combination. If the family 
Xylotomce or Thereuidce , represented in the British Fauna by the single 
genus Thereua , is not admitted, it would be better to associate this 
genus with the Xylophagidce , notwithstanding the different structure of the 
empodium and of the palpi, or even with the Leptidce. Mr. Walker has 
