354 EXPERIMENT STATION RECORD. 



accounts with illustrations and notes on tlie occurrence of the more important. 

 Other parasites of fowls briefly considered are the poultry mite (Dermanijssiis 

 gallinw), the common hen flea {Ceratophyllus gallince), the southern hen flea 

 (EcMdnophaga gaUinaceus sen Xestopsylla gaUinacea), the harvest mite (Trom- 

 hidium sp.), and a tick that infests turkeys, namely, Hwrnaphysalis chordeilis, 

 which has been found to occur in Warren County, N. Y. The bulletin con- 

 cludes with a brief account of methods of controlling the parasites of domestic 

 fowls. 



A new wheat thrips, E. O. G. Kelly {U. 8. Dept. Agr., Jour. Agr. Research, 

 i {1915), No. 3, pp. 219-22 J, , pi. l).—lt is stated that a new thrips, described 

 by Hood in 3914 from material collected by the author in 1908 as Prosopotlirips 

 cognatus (E. S. R., 30, p. 658), frequently becomes injurious to wheat {Triticum 

 spp.) in localized areas, but has not as yet been discovered to injure other grain 

 crops. This species of thrips is known to occur in all parts of Kansas, even to 

 the western border ; in Oklahoma ; at two places in western Missouri ; and in one 

 locality in extreme southern Nebraska. Careful search has failed to detect it 

 in northern Texas, eastern New Mexico, western Nebraska, and in Kentucky, 

 Tennessee, and Georgia. 



The eggs, which are deposited in the tissue of the young leaves of wheat or 

 grass, hatch in from 6 to 10 days. The larvte become full grown in from 10 to 

 12 days and crawl down the plants into the soil where they pupate and trans- 

 form to adults. The pupal period occupies from 10 to 13 days while the newly 

 issued female requires but from 2 to 3 days to prepare for egg laying. A few 

 adults are said to have lived for a period of S months in the laboratory. There 

 are from 4 to 5 generations of this species each year which overlap one another 

 so that adults and larvse are present at all times, even in late winter. 



Wheat plants furnish its princijDal food from the time the volunteer plants 

 sprout in August until the crop is harvested the following June. During the 

 interval between wheat harvest and the sprouting of volunteer wheat the thrips 

 feed and reproduce on Agropyron smithii, Elymiis canadense, E. virginicus, 

 Syntherisma sangidnalis, Paniciiin crus-galli, and Hordeuni jubaUim, upon 

 which they may also be found at all seasons. The injury by this thrips is con- 

 fined to the leaves of young plants, unfolding heads and newly formed grains 

 of wheat, and the young unfolding leaves of some grasses. " The leaves when 

 attacked by a dozen or more individuals at one time become badly mutilated in 

 a few hours and, owing to the influence of sunshine and wind, soon acquire a 

 * rusty ' appearance. Since the injured leaves nearly always cover the next un- 

 folding leaf, the injury often becomes disastrous to the i)lant by preventing the 

 new shoot from developing. The heads are first attacked when in blossom, the 

 pollen being eaten greedily. The tender stamens and pistils are lacerated badly 

 and dry up very quickly, so that the embryo seeds are killed in a kind of injury 

 seldom observed and one wherein the damage can hardly be estimated, although 

 evidently it is considerable. As soon as the grains begin to form, the thrips 

 attack the husk, and later, gaining access to the husk, they lacerate the tender 

 integument of the newly forming grain. Grains attacked at this stage are prac- 

 tically destroyed, and even after the milk has become a dough the injury causes 

 the grains to shrivel." 



It is stated that at the present time no thoroughly practical remedy can be 

 offered for the control of this pest, although large numbers may be destroyed by 

 burning ofl:" all grasses. 



Control of the citrus thrips in California and Arizona, J. R. Horton 

 (U. 8. Dept. Agr., Fanners' Bui. 67Jf (1915), pp. 15, figs. 7).— A popular sum- 

 mary of means of control of the citrus thrips, accounts of which by Jones and 

 Horton have been previously noted (B. S. R., 25, p. 657). 



