6o4 Journal of Agricultural Research voi. xii, N0.9 



setose; striae irregular, with strong isolated punctures; entire surface covered 

 with tubercles which are largest on the third, fifth, and seventh intervals. 



Front coxae contiguous. Prostemum strongly arcuately emarginate. Meso- 

 stemal coxae narrowly separated. Intercoxal piece of first abdominal segment 

 broad and deeply punctate. Second segment as long as third and fourth together. 



Type. — Cat. No. 21613, United States National Museum. 



WEEVILS WHICH AFFECT SWEET-POTATO TUBERS 



At least four species of weevils attack the tubers of the sweet potato — 

 namely, Euscepes batatae Waterhouse, Cylas formicarius Fabricius, C. 

 turcipcnnis Boheman, and C. jemoralis Faust. The adults of Euscepes 

 and Cylas can not be confused. Those of Cylas are differentiated 

 as shown in the "Table of sweet-potato weevils of the genus Cylas," p. 

 605. The pupffi of Cylas can be recognized from the fact that the direction 

 of the appendages is anteriad, while in Euscepes it is posteriad. Refer- 

 ence to the illustrations will be of great assistance in separating them. 

 The larvse can not be so easily distinguished, as both are of the same 

 general shape. It will be noticed, however, that they have quite a 

 different system of abdominal folds. The larva of Euscepes is more com- 

 pact. That of Cylas, when alive, is often attenuate and tightly drawn 

 so that no folds can be distinguished. When killed in a liquid which 

 shrinks it slightly, however, it will be noticed that the praescutal areas 

 are proportionately larger and often subdivided transversely. The 

 praescutum of Euscepes is not subdivided. This sclerite is the anterior 

 sclerite of a segment and almost always has a few tiny hairs. The only 

 other dorsal sclerite with hairs is the scutellum. In Cylas the scutellum 

 adjoins the praescutum, and the scutum is only lateral. In Euscepes 

 the scutellum is separated from the praescutum by the scutum. 



FAMILY APIONIDAE LE CONTE (1876) 



Subfamily Cyladinae Pierce (1916) 



genus cylas latreille (1802) 



Cylas Latreille, 1802, Hist. Nat. Gen. et Part. Crust, et Insects, t. 3, p. 196. 



Type. — Cylas brunneus Fabricius, monotypic. 



This genus contains twenty named species, of which two are widely 

 known under the names formicarius and turcipcnnis. There is consid- 

 erable confusion about these two species, due in part to the claims of 

 lyC Conte and Faust that they are synonymous. Fabricius described a 

 piceous-brown Indian species with reddish thorax as formicarius; Olivier 

 illustrated the species as almost pink but described it as brownish; 

 Schonherr cited it as piceous; Gyllenhal described a species from Java 

 with greenish-blue elytra, red thorax, and black head as turcipcnnis; 

 Labram and Imhoff illustrated a blue species under this name. Finally 

 Wagner presented an illustration of a species with green elytron as 

 turcipcnnis, and he probably is right. The bluish species was named 

 elegantulus by Summers. It is a common sweet-potato weevil. If it 



