ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 37 



contain that of birds or reptiles. For G. tachinoides the large yellowish- 

 brown bat is probably the chief source of the mammalian blood supply 

 An individual tsetse has been known to fly four miles, but except in this 

 case none returned home from a distance of over two miles. About 

 59 p.c. returned to the riverside when removed for a mile along the high- 

 way. Tsetse flies are destroyed by spiders and dragon-flies, by wasps 

 {Bemhex), but especially by Asilida?. J. A. T. 



Life-histories of Californian Coccinellids. — Curtis P. Clausen 

 {Univ. GaJifornia PuhUcations, Zoology, 1916, 1, 251-99). The periods 

 in the life-history of an Aphis-eating Coccinellid in normal summer 

 conditions in California are as follow : — Egg stage, 5 days ; first larval 

 stage, 5 days ; second, 3 days ; third, 3 days ; fourth, 6 days ; and the 

 pupal stage, 5 days. The number of eggs to be expected under normal 

 field conditions will vary from 200 to 500, or occasionally more, extend- 

 ing over a period of 4 to 8 weeks where the female lives the full adult 

 life under optimum conditions. The period between emergence and 

 mating is 1 to 3 days ; from mating to oviposition, 8 to 11 days. Ovi- 

 position normally occurs daily. Only one fertilization is necessary 

 during the life of the female, fertile eggs having been produced in one 

 instance 55 days after mating. J. A. T. 



Mouth-parts and Mode of Feeding in Louse. — A. D. Peacock 

 {Parasitology, 1918, 11, 98-117, 1 pi., 6 figs.). A detailed account is 

 given of the mouth, buccal funnel, pumping-pharynx, pumping-pharyn- 

 geal tube, pharynx, oesophagus, stabber-sac, Pawlowsky's glands, stabbers 

 and salivary glands. In feeding, the contraction of the buccal and 

 pumping-pharyngeal protractors causes the food canal and stabber-sac 

 to be brought forward. The buccal funnel and the attached pumping- 

 pharynx are brought forward. The dental region becomes everted, so 

 that the hood-like haustellum and the teeth are placed externally'. The 

 post-dental region comes to touch the skin of the host. The elements 

 of the pumping-pharyngeal tube also touch the skin ; the elements of 

 the sac tube are also brought forward to this point ; the contraction of 

 the sac protractors brings the stabbers into play and also influences the 

 sac in a complex way which is tentatively indicated. The structure of 

 the tips of the stabbers produces a lacerated wound. The buccal teeth 

 serve as anchors, but may also help to stretch the skin of the host. The 

 saliva may stimulate hiemorrhage from the wound or prevent coagulation 

 of the blood in the insect. Pawlowsky's glands probably produce a 

 lubricant for the stabbers. The afferent channel for the blood is possibly 

 formed anteriorly by the half-tubes of pumping-pharyngeal tube and 

 the buccal arch, and posteriorly of the pumping-pharyngeal tube alone. 



J. A. T. 



Biology of Lice. — George H. F. Nuttall {Parasitology, 1919, 

 201-20, 1 pi, 1 fig.). Experiments with Pediculus humanus show that 

 hce, when illuminated by rays of light falling vertically upon them, seek 

 the shade, and a black surface in preference to a light one. In warm 

 weather black clothing is inimical to lice, for it absorbs the maximum of 

 heat rays, and the parasites seek a cooler place. Moreover, the increased 



