ENTOMOLOGY. 57 



received from Japan. Rrontioii is also made of a new species of Telenonius 

 reare«l in Kussia from s'l'^^.v nioth eggs. 



"Only two ;)f the species, namely. .1. hif(isciati<.'< and N. kiirniKr appear to be 

 of primary importance, bnt it is obvions that once acclimatized these two species 

 will i)erform a very considerable part in the reduction in numliers of the gipsy 

 moth in the United States." 



Observations on some European ants, W. M. Wheeler {Jour. N. Y. Eat. 

 Sac, n (I00f>). No. .'i, pp. 172-187, figs. 2). — Notes are given on 3 parasitic ants 

 {Foniiicd riifd, t<troupy1ognathus hubcri. and )S. hnbcri alpinus n. subsp.) 

 observed in Switzerland and Italy, and a diminutive nonparasitic form, that 

 occurs on tlie Island of IJdo near Venice. 



A predaceous :nite proves noxious to man, F. M. Webster ( U. 8. Dept. Ayr., 

 Bur. Kilt. I'irc. US. pp. 2'/, figs. 13). — This is an account of Pcdicitloidcs rcii- 

 // /ro.s».s-, a supposedly beneficial mite which has become an external parasite of 

 man as previously noted from other sources (E. S. R., 21. p. 587; 22, p. 7s:>). 

 The occurrence of this parasite, its importance as a beneficial predator and as 

 a parasite of man, and its life history and habits are described at some length. 



The epidemic of dermatitis, which occurred in the vicinity of Philadelphia, 

 has been traced to this mite, which had increased rapidly, due to the abnormal 

 infestation of wheat by one of its hosts, the Angoumois grain moth. ITpon 

 the emergence of the moths that infest the grain, they remain in the straw after 

 threshing and are left to perish from star\ation; thus when infested straw is 

 used in the manufacture of mattresses, they make their way through the cover- 

 ing and attack the first animal host met with that furnishes food. Numerous 

 instances are reported in which persons have thus been attacked. 



In many of these cases, the wheat jointworm (Isosoma tritici) has been 

 found to be responsible for the presence of the mite. Investigations carried 

 on " at Lafayette. Ind., during December, 1909, and January and February, 

 1910, show that where straw is kept in masses, as in stacks and barns, the 

 mites literally swarm through the straw, and as soon as an Isosoma or its 

 parasites attempt to gnaw their way out through the cells in the straw, the 

 mites enter and kill them before they are able to enlarge the opening sufficiently 

 to enable them to make their escape ; indeed not more than 5 per cent succeeded 

 in escaping." The mite has thereby prevented Diptropinotus aureoviridis and 

 other jiarasites from controlling the jointworm. 



Investigations made in 1909-10 show that a period of from G to an indefinite 

 numlter of days elapses between the time the female mite emerges from the 

 abdomen of the mother until it produces young, depending upon the temperature. 

 " For a temperature of from 90 to 100° F., 6 days elapses; for a temperature 

 of from SO to 90°, 7 days elapses; for a temperature of from 70 to 80°, 9 days 

 elapses; for a temperature of from 60 to 70°, 13 days elapses; and for a tem- 

 perature of from 50 to 60°, 28 days elapses. With temperatures lower than 

 50° it is doubtful if the mites would develop. . . . The life of the mites varied 

 from 18 to an indefinite numl)er of days; 43 days was the maximum age for 

 those kept tmder the lower temperatures. The number of young produced by 

 a single female varied considerably and variation was greater among individuals 

 under like conditions than among those under variable conditions." 



A predaceous and supposedly beneficial mite, Pediculoides, becomes noxi- 

 ous to man, F. M. Webster (Ann. Enf. Soc. Anirr.. .i (t'.)IO), .Yo. /, pp. 15-39, 

 pis. 3). — This account is substantially noted above. 



The transmission of the typhus fever of Mexico (Tabardillo) by means 

 of the louse (Pediculus vestamenti), II. T. IvKKETts and II. M. Wilder {■lour. 

 Anicr. Mrd. Assoc, 5', {V.)10). \o. 16, pp. 1 30 '/-1 307 ).—riw following summary 

 and conclusions are drawn from the investigations here reported: 



