The name Linnaemya has been used in America and to a lesser extent in Europe for a collection of rather distinct elements linked together by the following characters:

Large robust forms, 8-15 mm. long; eyes densely haired; antennae large, the third segment truncate at the tip; second aristal segment somewhat elongate; palpi reduced in length, as long as the second antennal segment or reduced to mere papillae; epistoma strongly warped forward, the antennal and oral margin axes about the same length; bend of the fourth vein with a strong appendage, the apical cell open far before the wing tip; abdomen stout, bearing at least one pair of discal bristles on the intermediate segments.

In a previous paper I discussed the character of the female genitalia of the genus Hydriomena in general and more particularly in connection with the glaucata-crokeri group. In the present paper I offer further notes on certain other species of the genus which I have lumped roughly into the ruberata group. All these species show in the male genitalia a deep excavation between the forks of the uncus; each fork tends to broaden toward its apex which is evenly rounded and not bent downward nor pointed.

I attempted in 1939 to gather data on the life history of this cockroach. I was carrying on similar work on the wood-roach, Parcoblatta pennsylvanica Deg. and the American cockroach, Periplaneta americana L. However, B. germanica were so quick in their movements and escaped so easily, that I found it necessary, since my laboratory is in my home, to abandon the project. Some data were gathered, however, before the project was abandoned, on the period of incubation and the length of life of the immature roaches.