77 



lished. This conclusion permits us to search for the origin of the 

 natural color of silk in the green coloring- matter of the leaves. 



The silk is white because no coloring matter has been al)le to pass 

 through the walls of the silk gland. In the green silks it is the chlo- 

 ro])hyl of the leaves which passes through. We have, in fact, proven 

 that with a species which has green silk {Antheraia yaiixi-iiKil) the 

 blood has the chlorophyl spectrum. The yellow pigment contained 

 in the blood of the yellow species is identical, as has already been 

 shown by R. Dubois and L. Blanc, with that of the mulberry leaves, 

 and comes directly from these leaves. 



It is not to be supposed that the coloring matter of silks can be 

 made with the animal itself, as the negative results of attempts with 

 artificial coloration have shown. 



SOME PRELIMINARY NOTES ON THE CLOVER-SEED CHALCIS-FLY. 



By E. S. G. Titus. 



During the latter part of the past summer a study of the life histor}- 

 of the clover-seed chalcis-fly was taken up, and in answer to letters sent 

 to several correspondents of this office there were received packages of 

 ripe and ripening cloverheads from various localities in the United 

 States. Clover heads were al^^o received from various other sources. 

 The majority of these were found to be infested with the clover-seed 

 chalcis-fly {Bruchophagns fanebris How.), by the clover-flower midge 

 {Cecldomyla legum.hiicoJa Lint.), and in several instances both insects. 

 The chalcis-fly was reared from clover heads from the following 

 localities, the name in parentheses indicating the collector of the 

 clover heads: Hanford, Cal. (F. Benton); Fort Collins, Colo. (L. A. 

 Titus); Marengo, 111. (E. M. Wright); Urbana, 111. (F. M. Web- 

 ster); Winona Lake, Ind. (F. Benton); Richmond, Kans. (E. C. 

 Gentry); Agricultural College, Michigan (R. H. Pettit); Agricultural 

 College, Mississippi (Glenn W. Herrick); St. Anthony Park, Minn. 

 F. L. Washburn); Quaker Street, N. Y. (C. H. Moore); Corvallis, 

 Oreg. (A. B. Cordley); Providence, R. I. (F. C. Pratt); Burlington, 

 Vt. (G. H. Perkins); Pullman, Wash. (C. V. Piper); Danville, Va., 

 Virginia Beach, Va. , and District of Columbia. 



From some alfalfa seed from Mr. L. L. Marsh, P^nosburg Falls, 

 Vt. , received through the Bureau of Plant Industr3^ three specimens 

 of this chalcis-fly were reared. 



In order to obtain with any certaint}^ the full life history of these 

 species it was necessary to rear them isolated from each other. A 

 small area of clover, growing wild in the Rock Creek bottoms, was 

 selected and several clover plants were covered with breeding cages. 

 All budded and advanced flowerheads were removed. Owing to the 

 late date at which the experiment was started only a few more heads 



