NOTES ON THE BIOLOGY OF RELATED WEEVILS. 41 



The following notes bear upon the biology of certain of the Texas 

 weevils. The determinations are by Messrs. E. A. Schwarz, W. H. 

 Ashmead, and J. C. Crawford, in those groups respectively in which 

 they are specialists. 



ANTHONOMUS DISJUNCTUS Lee. 



This species was found breeding in large numbers on Heterotheca 

 suhaxillaris at Jacksonville, Tex., by Mr. C. R. Jones and the writer. 

 It oviposits in the bud at the base thru the involucre. The presence 

 of the weevil is indicated by the blackening of the two or three involu- 

 cral bracts which were punctured. The larva feeds among the seed 

 in the seed-head, and forms a compact cell of its exuviae. Here it 

 pupates and the adult emerges from the dried head. 



PARASITES. 



Three pteromalids were bred from a few buds brought in to the 

 laboratory. 



ANTHONOMUS FULVUS Lee. 



Mr. W. W. Yothers has carried out an extensive series of notes on 

 the biology of Anthonomiis fidvus incident to his finding the host 

 plant of this species. On June 9 the first weevils were taken, and 

 found to be yqyj abundant on the flowers of the purple mallow, 

 Callirrhoe involucrata. This was, then, the weevil that had been 

 sought so long — a native insect infesting a close relative of the cotton, 

 and with life history parallel in all details to that of the boll weevil. 

 The questions at once arose as to whether the new weevil was held in 

 check b}^ parasites which might be transferred to the boll weevil, 

 whether it had more than one host plant, whether it would feed on 

 cotton, and whether the boll weevil would feed on the mallow. 



The work of the season of 1905 answered some of these questions, 

 but not the one of primary interest. Only one parasite was bred, 

 viz, Bracon m,ellitoT^ already known as a primary parasite of Anthono- 

 mus grandis. If this parasite was not originally parasitic on A. grandis 

 and was so on A. fulviis we may reasonably expect that any other 

 primar}^ parasite of the latter may be induced to transfer its energies 

 against the former. 



The host plant, Callirrhoe involucrata^ is largely distributed over the 

 Mississippi River basin, and its guest, Anthonorrtus fulvus^ is known 

 by previous record to occur in Kansas and by observations of this 

 laboratory to breed at Ardmore, Ind. T. (C. R. elones, collector), and 

 Dallas and Victoria, Tex. Thus it is highly probable that the weevil's 

 range is at least coextensive with the range of this host plant. 



The plant is a spring bloomer, thriving in May and June in Texas 

 and gradually later toward the north. According to the laboratory 

 7036— Bull. 63— Oy 4 



