56 EXPERIMENT STATION RECORD. 



different healthy calves, no animals became infected. The experiments were 

 repeated with 200 freshly canjjjht CI. palixiliK, and after 20 days, when the flies 

 had fed on 5 healthy animals without producinj; illness, they became infective. 



Experiments were conducted to determine whether infective flies (d. paliiaUs) 

 convey Triiininoxoma gamhicnse to a healthy animal once only (mechanically) 

 or are al)le to infect many animal.s. out- after another, in the course of several 

 days or weeks. From the results obtained the author concludes that transmis- 

 sion is not merely mechanical but that the Glossintc are true hosts of the 

 trypanosomes. He succeeded in infecting flies hatched out from pupte by feed- 

 ing them on sick monkeys and in thus conveying sleeping sickness to several 

 healthy ones. It is concluded that the developmental period in the flies may be 

 shorter than the 20 days he had assumed it to be from his first experiment. 



Further investigations on the etiology of sleeping sickness, Kleine (Deut. 

 Med. Wcliiisclir., S.') (11)09), Xo. 2D, pp. I,i57-IM0, fiij-s. .'/..^• abs. in Sleeping 

 Sickncs.'i Bur. [London], Bui. 9, pp. 321-323). — In continuation of investigations 

 noted above, 410 flies were fed on infected animals. Of these 22, or 5 per cent, 

 became infective, but as about half die early in captivity the author thinks the 

 percentage may be doubled. The limit of infectivity of the flies has not been 

 determined. A captive Olossina morsitans, however, was found to convey trypa- 

 nosomes after S3 days. Emphasis is placed on the fact that all the author's 

 observations were made on fiies bred from paipse. 



Siphonaptera observed in the plague campaign in California, with a note 

 upon host transference, G. W. McCoy iPul). llaiUh and Mar. Hosp. Scrv. U. S., 

 Pub. Health Rpts., 2Ji {1909), No. 29, pp. 1013-1022).— The author presents in 

 tabular form the results of identifications of fleas taken on various small mam- 

 mals during the campaign against rodents for the purpose of exterminating the 

 infection of plague among these animals in California. There were identified 

 12,347 fleas representing 18 species. The large majority of fleas were found 

 associated with their pi'oper hosts, but there was some accidental distribution 

 to adventitious liosts. Rat fleas were found several times upon squirrels and 

 the squirrel fleas uimn rats. 



Some insects injurious to truck crops. The Colorado potato beetle in 

 Virginia in 1908, C. H. Popenoe {U. S. Dept. Agr., Bur. Ent. Bui. 82, pt. 1, pp. 

 8, pis. 2). — This is an account of the investigations of the life history and 

 methods of control of the Colorado potato beetle in the tide water region of 

 Virginia, conducted in cooperation with the Virginia Truck Experiment Station. 



This section of Virginia is considered as probably the greatest center for 

 the production of early potatoes in the eastern United States. Two crops are 

 raised in a small portion of this area, but over the greater part only a single 

 planting is made, this being made during the latter part of February and the 

 first of March and the crop of new potatoes being harvested in June. As the 

 early blight does little injury to the plants, the Colorado potato beetle becomes 

 the worst drawback to the culture of the potato in this locality. The methods 

 of control practiced are said to be very crude. 



In general the life history agrees with the description by Chittenden pre- 

 viously noted (E. S. R., 19, p. 159). In 1908, 3 generations or broods were 

 reared during the summer and very young larvje were seen on the tomato 

 at Norfolk as late as September 1. The period of {estivation which generally 

 follows the second generation in this species was shortened to 4 days in the 

 beetles which were carried through the stages at Norfolk. The beetles which 

 pass the winter are usually those of the third generation. On warm days with 

 an offshore wind great numbers of the hibernated individuals are blown or 

 carried out to sea where they perish, the beach often being covered with wind- 

 rows of the dead beetles. 



