560 EXPERIMENT STATION RECORD. [Vol. 43 



rapidly. Althouf,'li tbere may be several other important reasons wliy there 

 were so few apliis in 1919, tlie ladybird beetles were undoubtedly a large 

 factor in keeping them in control. Tlie author concludes that the practice of 

 storing ladybird beetles and liberating them in the spring sliould be continued 

 and more data collected to prove that they control the aphis. 



Direct sunlight as a factor in forest insect control, F. C. Ckaighead 

 (Proc. Ent. Soc. Wash., 22 (1920), No. 5, pp. i06-iOS).— Experiments conducted 

 show that borers attacking logs are killed by exposure of the logs to sunlight. 

 Control was obtained by turning the logs weekly during June, .Tuly, and 

 August. 



Banana root-borer, G. F. Moznette {Jour. Ayr. Research [U. S.], 19 (1920), 

 No. 1, pp. 39-46, i)Is. Jf, fig. 1). — The existence of Cosmopolites sordid us Germar 

 in Florida was brought to the author's attention in December, 1917, by the 

 receipt of specimens from a grower near Larkins, in Dade County, where they 

 were causing serious damage to banana plants. Eradication and inspection 

 work by the Florida State Plant Board was begun at once, and a national 

 quarantine was placed on this species April 1, 1918. It was found that the 

 infested plantings at Larkins had been made four year previous to the dis- 

 covery of the weevils with plants originating in a nursery in southern 

 Florida. This led to investigations which showed the presence of the weevils 

 at the nursery, and every effort was made to exterminate them. While it 

 could not be determined how the pest found its way into Floi-ida, it is thought 

 to have come in with sprouts or young plants introduced for propagation. This 

 species confines itself almost entirely to the banana, attacking all varieties, 

 but has been reported to attack sugar cane. It is quite widely distributed in 

 the Tropics, occurring in the West Indies, Brazil, the Philippines, Fiji, India, 

 Java, Ceylon, New Guinea, China, Borneo, Sumatra, Queensland, the Straits 

 Settlements, etc. 



The young suckers attacked by the borers wither and die in a short space of 

 time, due to the feeding and tunneling of the larva^ between the lateral roots 

 and the bulb, thus cutting off the flow of sap to the plant. The adult weevils 

 are found in the soil about the root and also under loose fiber surrounding 

 the base of the stem, at the crown. They congregate in the cavities caused 

 by the larvse at the base of the bulb of the plant. Technical descriptions of 

 the several stages of this species by W. D. Pierce are incorporated. The 

 eggs are deposited in the tissues, usually in the small compartments in the 

 sheaths or stem but occasionally being laid loosely in the slightly decayed 

 leaf sheaths close to the liealthy fleshy banana bulb, from which place they 

 enter the bulb. The incubation period of the egg was found to be from 5 to 

 7 days. On hatching out, the larva* cat their way into the body of the bulb 

 or the trunk. The work of the larvae is particularly destructive, since they , 

 girdle the plant in the immediate vicinity of the lateral roots put out fromj 

 the bulb of the plant, thus cutting off tlie passage of the sap. They may be'' 

 found tunneling into the main trunk as far as the heartwood, usually working 

 below ground, but in a few instances have been found in tlie trunk as high as 

 2 ft. above ground. The larval stage was found to extend over a period of 

 fnmi 15 to 20 days. While not observed by the author, the pupal period was 

 found by Jepson in Fiji to extend from 5 to 8 days. The pest is a difficult 

 one to control, and where plants are found infested in Florida and elsewhere 

 in the United Stales, they should be destroyed immediately and traps laid by 

 using strips of healthy banana trunks. 



The banana weevil (Cosmopolites sordidus Chevr.), H. Tryon (Queens- 

 land Agr. Jour., IS (1920), No. 5, pp. 222, 223).— This is a continuation of the 



