100 HETEROMERA. [Sitaris. 
narrowed towards apex, and the legs more elongate; last ventral seg- 
ment of abdomen longitudinally cleft, and penultimate segment emar- 
ginate. 
Female with the antenne much shorter, slightly thickened towards 
apex, and the legs less elongate ; last ventral segment of abdomen 
entire, 
In and about the nests of Anthophora ; rare, but has once or twice been found in 
some numbers; old wall at Hammersmith (S. Stevens); Weston on the Green, 
Oxfordshire, in nests of Anthophora retusa (Matthews); Stephens records it from 
Ken‘, Chelsea, New Forest, Oxford, Devonshire and Warwickshire. 
LYTTA, Fabricius. (Cantharis, auct nec L.) 
This is a very large and extensive genus, containing about two hun- 
dred and fifty species, which are very widely distributed, and range from 
Siberia to South Africa, India and Brazil; the majority, however, are 
found in warm or tropical countries; they are remarkable for their 
vesicant or blistering properties, and are widely used in medicine; the 
type of the genus is L. vesicatoria, which is the only species found in 
Britain : it is, however, very rare in this country, but its ordinary name, 
the ‘Spanish fly,” shows that its home is in the south of Europe, 
where it is found in great abundance about the middle of summer, 
frequenting the ash, privet, syringa, lilac, &c., and emitting a very 
powerful odour; only nine other species occur in Europe ; the important 
genus Mylabris (Zonabris, Har.), is not represented in our country ; it 
contains upwards of three hundred species, of which between forty and 
fifty occur in Europe ; several of the species have vesicatory properties, 
but they do not appear to be quite as strongly developed as in Lytta. 
The species of Lytta are elongate and elegant insects, which in many 
cases are very brightly coloured; they may at once be known from 
Meloé and Sitaris by the long parallel-sided elytra, which have a straight 
suture and are not divaricate, being at most a little parted at apex; the 
head is large, and the antenne filiform, with the second joint very small; 
the eyes are transverse and slightly emarginate; the palpi have the last 
joint ovate ; the thorax is not margined and is transverse and gradually 
narrowed behind ; the scutellum is large and inserted in the neck of the 
elytra ; the legs are long with the last tarsal joint cylindrical and not bi- 
lobed ; in the males the anterior tibiz are furnished at apex with a very 
strong broad spur, and the first joint of the tarsi is notched so as to enable 
the insect, with the help of the spur, to retain hold of the antenne in the 
female ; the anterior tibie in the female terminate in two spurs, and 
the first joint of the tarsi is not emarginate; the peculiar principle of 
the insect is termed Cantharidin, and, as recorded by Westwood, on the 
analysis of Robiquet, is a white substance in small crystalline plates, 
insoluble in water, but soluble in boiling alcohol ; owing to its volatility 
and very active properties great care has to be taken ia its preparation ; 
