1917] ECONOMIC ZOOLOGY — ENTOMOLOGY. 851 



of the world have reported the finding of an organism in typhus-infected lice. 

 This organism they believe to have a causal relationship to typhus fever. 

 Owing to the fact that improper methods have been used, culture of this 

 organism was impossible. In Mexico we have been able to grow this bacterium 

 and to show that morphologically, culturally, and serologically it is identical 

 with B. typhi-ex.anthcmatici." 



The lesser corn stalk borer, P. Luginbill and G. G. Ainsoe (f7. S. Dept. 

 Agr. Bui. 5S9 {1911), pp. 27, pis. S, figs. 6).— This is a report of studies con- 

 ducted by the senior author at Columbia, S. C, during the seasons 1913, 1914, 

 and 1915, and by the .iunior author at Lakeland, Fla., during 1913 and 1914. 



The phycitid moth Elasmopalpus lignosellus, which has heretofore occurred 

 in injurious abundance only in sporadic outbreaks, has now become of consider- 

 able economic importance in the Southern States. While particularly important 

 as an enemy of corn, cowpeas, sorghum, and beans, it also attacks chufa 

 {Cyperus esculentus) , crab grass (Eleusine indica), Japanese cane, Johnson 

 grass, milo maize, peanuts, sugar cane, turnips, and wheat. Though the larvae 

 are omnivorous, the investigations show that they have a decided fondness 

 for Graminese, and probably would confine themselves almost exclusively to 

 plants of this family if they were always obtainable. Crops grown on sandy 

 soils or soils lacking humus are usually the most seriously affected. 



The injury is caused by the larvse boring into the stems of growing plants 

 and feeding therein, such injury being particularly characteristic in young corn 

 and sorghum, where the larvse tunnel into the stalks at or slightly below the 

 surface of the ground, through and sometimes up the heart for a distance vary- 

 ing from 1 to 2 in. The bud leaves of the affected plants are severed from the 

 main plant, injury to corn in this manner resembling closely the work of the 

 southern corn root worm (Diabrotica 12-punctata) , but E. lignosellus is an 

 upland species, found only in the driest of soils, while the corn root worm breeds 

 generally in the moist lowlands. While some of the injured plants may survive, 

 they remain dwarfed or become deformed. In older corn, sorghum, and cow- 

 peas the damage consists primarily in the girdling of the stems at or slightly 

 below the surface of the ground, and the larvse also tunnel into the stems, 

 thereby weakening them to such an extent that very little pressure is required 

 to break them off. Cowpea plants have been found almost completely cut in 

 two at a point near or slightly below the surface of the ground by the larvse 

 girdling the stem, while in other cases the larvse were found tunneling into the 

 stems as in the case of corn and sorghum. The larvse in all stages spin a silken 

 thread wherever they go, and the younger ones readily suspend themselves by it. 



Originally described by Zeller in 1848 from Brazil, Uruguay, Colombia, and 

 " Carolina," U. S. A., this moth ig now known to occur in the United States 

 throughout all the Southern States, westward, including the southern parts of 

 New Mexico, Arizona, and California, and northward, including Oklahoma, 

 eastern Kansas, southeastern Nebraska, southern Iowa, Illinois, Indiana, and 

 Ohio, southeastern Pennsylvania, New Jersey, and along the Atlantic coast 

 into Massachusetts. 



Technical descriptions are given of its several stages, which include six 

 larval instars. Oviposition apparently does not take place when the tempera- 

 ture falls much below 80" F. The eggs, which are thought to be deposited on 

 the stems of plants, in the axils of the leaves, or on the ground at or near the 

 bases of the stalks, hatch in 3 days in summer, 5 days in early fall, and in 

 from 6 to 8 days in late fall. The number deposited under laboratory condi- 

 tions varied from 91 to 342, with an average of 190, as many as 73 eggs being 

 deposited in a single day. The larvse may reach maturity in 13.8 days, but 

 generally in about 16.8+ days during the summer months and from 22 -t- to 



