. Bulletin. Insects; Insect pests; Entomology; Insects; Insect pests; Entomology. FIELD WORK RELEASE OF PARASITES. 25 high hedge of Ambrosia trifda with scattered Solanum rostratum. As a further check on the experiment the nearest part of this field ("D," fig. 5) was examined and proved to be parasitized by per cent less than "; On the contrar}', the farther part of the field C'E," fig. 5) showed per cent higher parasitism than "; The conclusion was that "E" and "D" did not influence "; The results are given in Tabl
. Bulletin. Insects; Insect pests; Entomology; Insects; Insect pests; Entomology. FIELD WORK RELEASE OF PARASITES. 25 high hedge of Ambrosia trifda with scattered Solanum rostratum. As a further check on the experiment the nearest part of this field ("D," fig. 5) was examined and proved to be parasitized by per cent less than "; On the contrar}', the farther part of the field C'E," fig. 5) showed per cent higher parasitism than "; The conclusion was that "E" and "D" did not influence "; The results are given in Table XIV for the entire experiment, and also according to species. It is believed by the writer that it was the release of Bracon mellitor which accomplished the change. The evidence upon wliich tliis belief is founded is both positive and negative, Bracon mellitor was not found breeding upon any other species of weevil in the vicinity, and yet the examinations showed an increase of parasitization by this species in the "parasite TTON. Fig. 5.—Diagram of cotton plantation of H. 0. Samuel, Dallas, Tex., of 64*4 acres, showing location of plats where observations and experiments on boll-weevil parasitism were made. (Original.) area" opposed to a decrease in the "check ; Catolaccus incer- tus, although released in large numbers, did not take hold at all, nor was it found breeding upon any other species of weevil in the vicinity. A few Cera/mbycohius cyaniceps were released, but the only trace of parasitization by this species was found in the original check. And yet this species was bred from Lixus musculus in the stems of Poly- gonum pennsylvanicuTYi near by, and also from Trichoharis texana Lee, in the stems of Solanum rostratum adjacent to "A". No Eurytoma tylodermatis were released, although this species was abun- dant tlii-oughout the field. It is known as a parasite of Lixus scro- hicoUis Boh., which breeds in Ambrosia trifida stems. Immense
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