OBSERVATIONS ON INSECTS AND VERMES. 407 
BLATTA ORIENTALIS.—COCKROACH. 
A neighbour complained that her house was overrun with a kind 
of blackbeetle, or, as she expressed herself, with a kind of black- 
bob, which swarmed in her kitchen when they got up in a morning 
before daybreak. 
Soon after this account I observed an unusual insect in one of 
my dark chimney closets, and find since, that in the night they swarm 
also in my kitchen. On examination I soon ascertained the species 
to be the Alatta orientalis of Linnzeus, and the Blatta molendinaria 
of Mouffet. The male is winged; the female is not, but shows 
somewhat like the rudiments of wings, as if in the pupa state. 
These insects belonged originally to the warmer parts of America, 
and were conveyed from thence by shipping to the East Indies ; and 
by means of commerce begin to prevail in the more northern parts 
of Europe, as Russia, Sweden, &c. How long they have abounded 
in England I cannot say ; but have never observed them in my 
house till lately. 
They love warmth, and haunt chimney closets and the backs of 
ovens. Poda says that these and house-crickets will not associate 
together ; but he is mistaken in that assertion, as Linnzeus suspected 
he was. They are altogether night insects, (Luc7/ue@), never coming 
forth till the rooms are dark and still, and escaping away nimbly at 
the approach of a candle. Their antenne are remarkably long, 
slender, and flexile. 
October, 1790. After the servants are gone to bed the kitchen 
hearth swarms with young crickets and young Blatte@ molendinarie 
of all sizes, from the most minute growth to their full proportions- 
They seem to live in a friendly manner together, and not to prey 
the one on the other. 
August, 1792. After the destruction of many thousands of Alatte 
molendinari@, we find that at intervals a fresh detachment of old 
ones arrives, and particularly during this hot season; for the 
windows being left open in the evenings, the males come flying in at 
the casements from the neighbouring houses, which swarm with 
them. How the females, that seem to have no perfect wings that 
they can use, can contrive to get from house to house does not so 
readily appear. These, like many insects, when they find their 
present abodes overstocked, have powers of migrating to fresh 
