490 JOURNAL OF ECONOMIC ENTOMOLOGY [Vol. 4 



are largely replaced by a number of smaller legumes, which also 

 support quite a series of bruchid species. In addition to these two 

 classes of legumes, there are a number of trees, as the locusts and 

 redbud, which also have their typical bruchid enemies. 



The particular interest of the men employed in the work was with 

 the parasites, and observations on the hosts were necessarily limited. 

 But as opportunity offered observations were made and recorded. 



At least eight of the species of parasites reared from bruchids are 

 known to attack the boll weevil. Of these Cerambycohius cyaniceps 

 Ashm. is, on account of its wide geographical and host range, by far 

 the most important. It has been definitely reared from at least 

 seven species of bruchids ranging from New Mexico to the District of 

 Columbia, and from many other hosts in stems, fruits and buds, as 

 well as from the boll weevil throughout the range of that species in 

 the United States. Of the latter host it is everywhere an important 

 enemy, becoming in some regions, notably southern Arkansas and 

 northern Louisiana, the dominant parasite. The bruchids have 

 undoubtedly been among the principal sources from which the boll 

 weevil has drawn its quota of this parasite. In fact, the nature of the 

 bruchid fauna, or rather, of the bruchid flora of the region mentioned 

 might well account largely for the dominance of this parasite as an 

 enemy of the boll weevil. As has already been stated, the leguminous 

 flora of southern Texas is largely small trees or shrubs, or in other 

 words, perennials. Their fruit is to a considerable extent indehiscent, 

 and affords constant opportunity for the breeding of bruchids. Thus 

 we find that a number of bruchids breed almost constantly in the 

 pods of such plants as the huisache (Vachellia farnesiana) and mesquite 

 {Prosojyis glandulosa). This furnishes the normal bruchid parasites 

 with an abundance of preferred hosts, and such species as C. cyaniceps 

 do not become so noticeable as parasites of the boll weevil. On the 

 other hand, the leguminous flora of the Arkansas-Louisiana region 

 is largely annual and the fruit dehiscent. This prevents the devel- 

 opment of more than two generations of bruchids in a year, one matur- 

 ing in the late summer and the other hibernating in pods prevented 

 from opening by the presence of the immature bruchids. This leaves 

 nearly the whole summer in which the parasites must either not breed 

 or must seek other hosts. The boll weevil, being the most abundant 

 suitable host, draws to itself many of these parasites, especially those, 

 such as C. cyaniceps, which are least particular as to the nature of 

 their host. An exactly similar case exists in eastern Louisiana, where 

 another chalcid, Catolaccus hunteri Cwfd., is the dominant parasite 

 of the boll weevil. This parasite is the species most abundantly 

 bred from the dehiscent pods of A cwan illinoensis, an annual legume, 



