BIOLOGIES OP WEEVILS CONTRIBUTING PARASITES. 4f) 



the conclusions in this regard may be more thoroughly understood, 



this subject must be introduced by a scries of brief biologies of nil 

 the weevil specie's which have contributed parasites to the attack of 



the boll weevil. 



CURCi l.ioNin.i:. \riii\i\ 1 . 



1. Apion decoloratum Sm. breeds in Meibomia particulate,. It is 

 parasitized at Washington, 1). C, by Catolaccus incertus. 



2. Apion griseum Sm. breeds in Phaseolus [xr< nn'ts, and is para- 

 sitized by the same species as the preceding. 



CURCl UOMWK. CLBONINI. 



3. Llxus muscuhiS Say makes a gall in the stems of Polygonum 

 pennsylvanicum. The larva 4 and pupae are found in these galls. The 

 weevil and its host plant are typical of the fall, the plant being 

 found in low moist ground, frequently in close proximity to cotton 

 iields. The weevil is attacked by two of the important boll-weevil 

 parasites. 



4. Lixus scrobicollis Say dwells in the stems of Ambrosia trifida 

 and psilostachya , two of the commonest roadside and waste-place 

 weeds throughout the country in summer and fall. The entire stem 

 is riddled by the weevil larvae, wdiich pupate in cells of frass at the 

 end of their burrows. Eurytoma tylodermatis and other parasites not 

 concerned in the discussion have been bred from this weevil. 



ERIRHININI. 



5. Desmoris scapalis Lee. breeds in the seed heads of Sideranthus 

 tuhiginosus, a summer weed, which is very abundant in some localities 

 along roadsides and on prairies. The larvae are expelled with the 

 seed and enter the ground for pupation, maturing in the following 

 spring. This species is parasitized by Bracon mellitor, which has a 

 much more rapid development than its host. (See PL III, B, D, F, G.) 



ANTHONOMINI. 



6. Anthonomus (Anihonomorphus) fulvus Lee. breeds in the buds 

 of Callirrhoe involucrata, an early spring mallow, which is common 

 in May and June on moist meadows. The larvae feed upon the floral 

 column of the bud or the imperfectly opened flower and pupate in a 

 cell of excreta in the capsule or fallen corolla. Bracon mellitor and 

 Catolaccus incertus have been bred from it. (See PI. II.) 



7. Anthonomus signatus Say, the strawberry weevil, breeds in a 

 number of rosaceous plants, such as strawberry, blackberry, raspberry, 

 and wild jose, as also in red-bud. It is an early spring weevil, ovi- 

 positing in the buds, which soon drop to the ground, where the larva 

 transforms to the pupa stage. It is parasitized by Catolaccus incertus. 



