June, 1889. 
WILD BEES. 
129 
twisted and small, the liind ones broad, folding up like a fan, 
and the eyes are placed on a stalk. The female has neither 
eyes, mouth, nor legs, and, with the exception of the flattened 
thoracic portion which projects from between the terminal 
abdominal segments, is entirely concealed within the bee. 
Generally only one is present in a single bee, but sometimes 
two or even three may be found. The degeneration which 
this sex has undergone is, of course, due to the fact that it 
has no need to leave its host; but as the sexes are parasitic 
in separate hosts the male has naturally not degenerated to 
the same extent. All the species are very minute, and the 
males may be obtained by keeping Andrenas alive in captivity. 
They are seldom met with abroad. The Strepsiptera also 
attack Halictus and other genera of bees, and in other 
countries Yespidce, Homoptera , and ants have been found 
stylopized. These insects are now generally considered as 
Coleoptera, and are placed near to the genus Meloe, which is 
parasitic on Anthopliora, and which in its life-history rather 
resembles Stylops. 
Stylops is ovoviviparous, and the larvae are at first active 
hexapods. They crawl about on the hairs of the bee, and 
when it visits flowers they get on to these. Undoubtedly, 
enormous numbers of these larvae, as also of Meloe, must 
perish, for they cling to and are carried off by any insect 
which may happen to visit the flower or to brush against the 
grass to which they cling. I have seen a specimen of 
Nomada so covered with the larvae of Meloe as to be quite 
unable to flv. 
•/ 
When, however, the active Stylops larvae have been trans¬ 
ported to the burrow of the species on which they are 
parasitic (as happens to but a very small proportion of their 
number), they make their way into the larva of their host, 
and then undergo an ecdysis which entirely changes their 
form. They lose their organs of locomotion, and become 
cylindrical maggots, feeding in the interior of the larva. 
They reach the pupa stage when their host is on the point of 
emergence, and then bore through the body of the bee. One 
could hardly find a better instance of the entire dependence 
of the form of the larva on its mode of living, for we see in a 
single species the active form occurring at first when the 
insect has to go in search of food ; then, when it is surrounded 
with all that it requires, it takes the maggot-like form which 
is always assumed under such circumstances. 
(To be continued.) 
