HALICTUS. 
219 
brought them forth in all the beauty of their gay attire, 
and that it was from their broods deposited thus in the 
spring and early summer, that the autumnal insects 
were developed. This theory is both plausible and pos¬ 
sible, and I have no doubt that it is the correct one; and 
thus is explained the total absence of males at the time 
of the appearance of the females in the foremost portions 
of the year; this habit we shall find also in the Bombi. 
The flowers they delight in, besides those previously 
named, are among others the ribwort plantain, and the 
bramble, as well as the Umbelliferce and the flowers of 
the broom. The females possess two remarkable dis¬ 
tinctions of structure not found in any of the other bees, 
which consist in an articulated appendage in the centre 
of the front margin of the labrum, and a vertical cleft in 
the terminal segment of the abdomen, both of which 
will necessarily have their uses in the economy of the 
insect, although what these may be has not been dis¬ 
covered. 
They, like Andrena , are exposed to parasites and 
enemies. The smaller species of Nomada infest their 
smaller kinds, and St. Eargeau tells us that the Sphe- 
codes are also parasitical upon them. The smallest of 
the genus, which is indeed an exceedingly minute insect, 
is subject to a very minute strepsipterous destroyer; 
whether this be a genuine Stylops I am not aware, but 
the supporting insect being so minute, in fact the 
smallest of our bees, how small must be the enemy bred 
within it! Another genus of this order has been found 
by Mr. Dale upon them, and which is figured as the 
genus Elenchus in Curtises ‘ British Entomology. ; The 
smaller species are also attacked, upon their return home 
laden, by spiders and ants. Chryses and Hedychra are 
