BEHAVIOR OF INSECTS OTHER THAN ANTS 411 



ease had slept upon beds made from wheat straw that had come 

 from a certain locaHty. When straw from one of these beds 

 was placed upon a human body the disease developed. Some 

 dust from the straw was placed 'upon a human body. The 

 disease developed at once. It was found that the same straw 

 when treated with chloroform did not cause the disease. This 

 indicated a living organism as the cause of the disease. A 

 microscopic examination of the dust from the straw showed 

 that it was infested with this mite. When these mites were 

 placed on the human body, the disease developed. 



De La Torre Bueno " relates that the water strider Micro- 

 velia hibernates beneath the overhanging banks of little streams 

 and that it breeds in early spring. Like all water striders, it 

 is carnivorous; but when live prey cannot be foimd, it will 

 feed on dead and gamey food. When near the bank, it moves 

 with quick, short steps; but when far from shore, it makes 

 rowing movements. The author gives a lengthy description 

 of the bug's method of cleaning itself. At mating time the 

 female is passive and the male aggressive. A careful aquarium 

 study was made of the oviposition and larval life of the bug. 

 The adults were confined to a large aquarium until they had 

 mated and oviposited. As soon as hatched, each larva was 

 isolated in a small individual aquarium and kept there until 

 mature. The adults mated between August 20th and 27th 

 and immediatel}' began to lay. Some eggs were attached to 

 duck weed, some were dropped upon the surface of the water; 

 but the majority were encased in jelly and attached to the 

 walls of the aquarium. The life cycle consisted of seven in- 

 stars; one embryonic, five nymphal, and one adult. The adult, 

 on first emerging, is creamy white. The author thinks that 

 there may be as many as five generations a summer. 



McDermott '' has made a careful field study of the phos- 

 phorescence of the following Lampyridae: Photinus pyralis, 

 P. Pennsylvannica, P. consanguineus, P. scintillans, Lecontea 

 angulata. He describes the flash of several species and in- 

 sists that its quality and mode of emission is of sufficient tax- 

 onomic value to permit the identification of the species on the 

 wing. He thinks that the glow is related to the sexual function 

 and that it has a protective value. He claims that the emission 

 of the flash is under the voluntary control of the species; but 



