105 
Osmia ænea Lin. builds in disused nests of Hoplomerus reni- 
formis in clay-walls. It divides each cell of tlie wasp in two by a 
partition and uses each of the two parts as a cell. The nest is 
closed by means of two stoppers, made, like the partitions of 
masticated vegetable matter. 
O. Solskyi Mor. builds in reeds on roofs. The cell is sepa¬ 
rated by partitions of masticated vegetable substance. On account 
of the slanting position of the nest, the partitions are shew; the 
fodder is stored up under the bottom of the cell, which on account 
of the position, is really the highest point in the cell, the larva 
eats from the lowest point upwards and ejects its excrements to- 
wards the entrance to the nests. It makes a cocoon and remains 
as larva in the position it has while eating, with the head averted 
from the entrance to the nest, but when in transforming i nto a 
pupa, it sheds the larval skin, it makes a turn, so that the head 
points towards the entrance to the nest, and the imago can after 
emerging eat its way straight out. 
Osmia maritima Friese is found in the sandhill districts along 
the coast of Denmark. The nest consists in a burrow formed ho- 
s 
rizontally into a sandhill, at the bottom of which one or two cells 
are found, sometimes' fixed to a small stone. The cell consists of 
masticated lichen mixed with minute stones. When half grown the 
larva commences to eject its excrements. 
According to my observations there is that difference between 
the larva of the Apidæ gastrilegidæ and of the Apidæ podilegidæ, 
that the former eject their excrements while growing an in a solid 
State, while the latter do not eject them until fully grown and 
then in a fluid state. 
O. fuciformis Nyl. Cells are found in sandhills. They are 
si milar to those of O. maritima but are found joined in larger 
numbers. 
