Mar. igoo.l DYAR : On THE LARV.t OF SaW-FlIES. 27 



seta ; the subventral tube from a large tubercle forming the projection 

 of the subventral ridge on which are several seta^ ; foot with small 

 seta^. All the tubercles are shaded with dusky black except in their 

 centers. Segments obscurely 2-annulate, the annulets minutely gran- 

 ular in the center. Body otherwise green, shining, smooth. The 

 glandular tubes form a row on the anterior edge of the cervical shield 

 and on joint 13, fringing the body; the anal plate is smooth. 



Cocoon. — Loose, irregular, of yellowish brown somewhat reticular 

 silk. Xo ultimate stage, the glandular tubes becoming shrunken on 

 spinning. 



Food-plant. — Desmodium. Found by Mr. A. Busck and the writer 

 in Alexandria Co., Virginia. Chain Bridge, ^'a. (Busck); Rosslyn, 

 Va. (Dyar). 

 Atomacera ruficollis Norton. 



No males have been bred, but they will probably prove to be A. 

 debilis Say when obtained, as originally suggested by ^^'alsh. 



The following notes are taken from the books of the Department 

 of Agriculture (no. 3198) and were written by A. Koebele. 



"August 24, 1883, found a small saw-fly larva on TT/yVjv/^v- mos- 

 cheutos L., sometimes two or three on one leaf. They are about 10 to 

 12 mm. in length, of a light green color on the upper side and 

 almost white on the under side ; head black ; a transverse row of 

 short black spines on each segment, longest in front ; stigmata black. 

 There is also a variety where the spines are not l)lack, but evidently 

 the same insect. Spun a (quadrangular cocoon." 



In the preserved alcoholic material the head is round, prominent, 

 brown black, a space in clypeus and mouth whitish; width i.i mm. 

 Antennas rudimentary, not joined. Body with segmentary rows of 

 stout, rather long, black tubes, somewhat longer on the thorax. 

 These are longer than in A. desniodii. Anal plate rectangular, dark 

 brown except at tip. Thoracic feet large, the thorax a little enlarged 

 laterally ; abdomen smaller, somewhat flattened, its feet small, on 

 joints 6 to 12 and 13. Feet all pale. There are a few minute set^e 

 which can hardly be deciphered in the specimens ; probably they are 

 as in A. desmodii. In the pale variety mentioned above, the head is 

 brown over the vertex, a (juadrangular patch in clypeus and eye black. 

 Body tubes colorless. Both species of Atomacera rest flat on the 

 venter like slugs, eating the parenchyma of the leaf from below. 

 They are slightly gregarious. 



