The European earwig (Forficula auricularia L.) accidentally introduced some years ago into the United States, is now abundant in several of the Western and at least one of the Eastern States; it has become established also in New Zealand, where, according to Tillyard, it has become a major pest, eating into peaches, nectarines, and apricots and rendering them useless for sale.

The swallow bug, Oeciacus vicarius Horvath, is of common occurrence in North America, chiefly, if not entirely, upon the cliff swallows, Petrochelidon lunifrons (Say); it has been recorded from the barn swallow, probably in error.

It appears to be really distinct from the European swallow bug, Oeciacus hirundinis (Linnacus).

The habits, structure, and specific characters of the bug do not seem to have been adequately studied hitherto.

This paper deals with the external structure of the bug and of such of its biology as could be worked out under the handicap that its natural host could not be kept in captivity.

The bugs attack man readily, but do not appear to adapt themselves readily to living upon man or in his dwellings.

During the summer of 1927 Mr W. J. Hamilton, a student in the Department of Entomology, Cornell University, collected biological material in parts of Cuba, Panama, and Costa Rica. He brought two small vials of parasites taken from bats. Though the collection contained only 24 specimens yet it is of interest on account of the rarity of some of the species. It is, therefore, thought worth while to offer the following brief notes on the species taken.

In July, 1927, Dr Kenneth Smith took a specimen of the Hippoboscid fly Ornithomyia avicularia on the window of a building at the Cambridge University farm. The fly was lethargic and easily captured, and, noticing that its abdomen was infested by some parasite, the captor kindly handed me the specimen.

Generic Diagnosis, ♀. Cephalothorax with transverse lateral expansions, small in young, resembling a hammer in old specimens, between whose anterior surfaces projects the head. Neck smooth, cylindrical and without swimming feet. Trunk much enlarged transversely, smooth, flattened dorsiventrally, bearing a pair of posterior appendages profusely and dichotomously branched. Abdominal appendages reduced to two small knobs; or one undivided abdomen.Egg-strings long and straight; eggs multiseriate. Two pairs of antennae, twopairs of maxillae, one pair of maxillipedes.

(1) Examination of the inmates of Government reformatories in the Highlands of Kenya showed a high incidence (57·9 per cent.) of very light infestations with hookworm, and an incidence of approximately 50 per cent, of Taenia infestations. Many of the latter are not detected by the usual microscopic examination.

(2) Treatment with carbon tetrachloride in doses of from 1½c.c. for children to 4 c.c. as the standard adult dose gave approximately 76·1 per cent, cures for hookworm, and in the case of boys with fairly light infestations with T. saginata an efficacy of approximately 97 per cent. In the case of 72 boys very heavily infested with Taenia 58 per cent. cures were effected by a single treatment with carbon tetrachloride and oil of chenopodium.

(3) A combination of carbon tetrachloride and oil of chenopodium appears to be a safe and efficacious anthelminthic for the common worm infestations of man in Kenya.

(4) Growing natives lightly infested with hookworm appeared to grow and increase in weight at a normal rate, and did not improve in physical condition after treatment.

(5) Boys in the same institution infested with Taenia progressed at a subnormal rate, but increased to a figure above normal after treatment, the increase appearing to be mathematically significant in spite of the small number of samples analysed.

In 1926 two of us published the results of a long series of experiments on the toxic action of the alkaloids of ipecacuanha in cultures of several species of entozoic amoebae. These experiments led us to definite conclusions regarding the differential susceptibility of the various species of amoebae studied, and the relative potency of several alkaloids employed. They also showed clearly that the full specific action of emetine, on susceptible amoebae, is only disclosed if the alkaloid is allowed to act for a sufficient time (two or three days.)

Material examined. A male and a female from Ramphastos brevicarinatus, Barro Colorado Island, Panama Canal Zone, collected by Mr J. Van Tyne of the University of Michigan, through whose kindness I have been enabled to examine them. The species was originally described from “probably Ramphastos tocard” (which is R. brevicarinatus) from Colombia. My material agrees with the original description and is probably correctly identified, although, as will be further considered, another species of the same genus occurs upon toucans.

There is still so much confusion with regard to the minute hexapod mites which have for ages plagued man in various parts of the world, and which are known popularly as harvest bugs, harvest mites, bête rouge, rouget, chigger mites, etc., that a review of our present knowledge of the matter may be of use in saving investigators' time in referring to a voluminous and widely scattered literature.