226 



The chitinoiis covering of the egg seems very impervious to water 

 evaporation or chemical action, but not to high temperatures, which 

 are therefore the most certain means of kilhng both lice and their eggs. 



Galli-Valerio (B.). Parasitologische Untersuchungen und parasito- 

 logische Technik. [Parasitological researches and technique.] — 

 CenlralbJ. f. Bakf., Parasit. ?/. IvfeldicnskranJih., Jena, Ixxvi,. 

 no. 7, 25th August 1915, pp. 511-518. 



Acarids of the genus Gh/ciphagus Avere found to be present in hay and 

 straw in the canton of Valais, where soldiers, using these materials, had 

 suffered from itching, thus corroborating Hering and ]\Tnrray's obser- 

 vation of these Acarids. The author has also noticed that Alpine 

 climbers suffer in the same way after sleeping on hay. Up to now,, 

 Psoroptes communif^ on the rabbit had only been found in the outer ear, 

 but an instance is recorded of a rabbit, the lips and toes of which were 

 attacked by Sarcoptes minor and P. commmiis. Experiments in the 

 resistance to starvation of ticks are recorded. A nymph of Ixodes 

 ricinus lived for two months on water and a little sugar ; of 150 

 Argas persicus, 13 died after eight months, 136 after 11|-, one after 13,. 

 nine after 16|-, one after 20| and two after 22-| ; they had previously 

 been allowed to suck blood from fowls. Specimens of Pediculus 

 capitis, De Geer {cervicalis, Leach), which were kept in test-tubes, died 

 after 12 hours at 36° C. and after three days at 20° C. In a woman's 

 hair, cut oft" and placed in a container at 20°, some of the lice died 

 after six days. 



SiKORA (H.). Beitrage zur Biologie von Pediculus vestimenli. [Contri- 

 butions to the biology of Pediculus vestimenti.] — Centralbl. f. 

 Bakt., Parasit. u. Infektionskrankh., Jena, Ixxvi, no. 7, 25tli 

 August 1915, pp. 523-537. 



In his researches on the biology of Pediculus humanus {vestimenti), 

 the author endeavoured to work under natural conditions, carrying 

 on his person, day and night, a small box containing glass receptacles, 

 in which the lice w^ere confined by plugs of cotton wool. Twice daily, 

 they were fed on the forearm or on the back of the hand. To confine- 

 them to the chosen spot, the skin around it was greased with vaseline 

 and it was found that individuals which became completely covered 

 with vaseline were quite unaffected, even 12 hours later. The lice 

 were subsequently kept in glass tubes 2 cm. long, of which one end was. 

 plugged with cotton wool and the other closed with silk gauze. For 

 the purpose of feeding them, these tubes were placed in holes in a piece- 

 of wood which was then strapped to the forearm. According to< 

 Warburton, the third moult is followed by an inactive stage of four 

 days, but the author considers that this must be due to the feeding 

 not having been done sufficiently carefully. Underfed or cold lice- 

 do not oviposit. In one case mating took place 10 hours after the 

 third moult and the first eggs were laid by the first three batches- 

 Avithin 24-48 hours. It is not probable that eggs are laid on straw 

 bedding under natural conditions, as oviposition ceases at 76° F. and a, 

 daily fall of temperature to 61° F., even though it lasted for two hours 

 only, caused a considerable reduction in the number of eggs. It i& 



