198 REPORT OF THE COMMISSIONER OP AGRICULTURE. 



The pupa is pale orange in color, witli a median yentral stripe of a 

 darker shade. Eyes blackish ; upper part of legs and wing casiis brown- 

 ish. The front border of the i)rothorax projects beyond the liead and 

 is quite deeply not-ched. Two long delicate hairs project anteriorly, and 

 the cxciirved thoracic horns noted in the pupa of ihe seed midge are 

 quite prominent. 



June 23, the first flies seen made their appearance. They proved to 

 be quite similar to the seed midge. The two most marked dilierenees 

 were that the average size was considerably smaller, and that while the 

 number of antcnnal joints in C. legrimenicolct was male 15 and female IG, 

 in C. trifolii it is male 15 and female 14. There were also manj- minuter 

 diflerences, as will be seen ui>ou comparing tlie technical descriptions. 



The leaf midge was quite common upon the department grounds, but 

 was not seen elsewhere. It is to be hoped that this notice of its pres- 

 ence will suffice to put our readers on the lookout for it. 



Fig, 5, PI. I, shows the midge and its work. We give below, in 

 small type, a translation of Dr. Low's original description of this insect 

 and its habits in the Verhroid lungen dcr ZooJoglsch Botaimclien Qesell- 

 scM/t, Wien, 1874, p. 143. 



Cecidomyia trifolii, Lowt. 



Male. — Head small; occiput and clypeus black Lrown, -n'itli Llack hairs, face brown- 

 ish, with yellow hairs ; eyes black, large, and on the margin bordered with pale hairs; 

 palpi small, yellow, and with yellow hairs; antennae I"'™ long, 14 to 15 jointed, dusky 

 brown, the scape joints globular, pedunculate, the end joint much smaller, peduncles 

 not quite as long as the joints, each joint with two whorls of yellow hair, of which 

 the foremost is long and the hindermost of half the length, each whorl regular and 

 forming a comidete circle; thorax reddish brown, scuteiium black brown, in some 

 lights shimmering gray, with black hairs and with two small, black, longitudinal fur- 

 rows, diverging forward, in which the hair is quite thick; nietasternum, shoulders, 

 sides of the thorax, and hinder poilions with yellow hairs; postscutellum reddish 

 brown with yellow hairs ; logs somewhat thin, brown, lighter on the inner side, ends of 

 joints and tarsi dusky, slightly shimmering from yellowish hairs, coxae reddish brown; 

 balancers pale yellow red ; wings 1.4™'" long, .7""" wide, scarcely clouded, strongly pris- 

 matic, somewhat thickly beset with brown hairs and with brown cilia, root of the wing 

 yellowish brown, costal rein, first and second longitudinal veins strong, black brown, the 

 third longitudinal vein delicate, grayish, first longitudinal vein very near the costal, 

 merging with it a short distance before the middle of the wing; second longitudinal 

 vein almost straight without any upward bend, toward its end it makes a scarcely 

 perceptible inclination forwards and ends in Ihe border before the end of the wing ; the 

 third longitudinal vein divides at half the length of the wing, the inner fork being 

 ehort, much bent, and forming, with the hind border of the wing, almost a right an- 

 gle, the outer fork almost right angled at the division, shortly carried forward ; wing- 

 fold indistinct; cross vein short., almost straight, beyond the middle of the first long 

 vein; abdomen reddish brown, ringed with black, beneath somewhat lighter; first 

 segment beneath reddish brown, all segments on their hinder border with an edge of 

 yellowish hairs, which are a little thicker on the underside ; claspers quite large, only 

 a little lighter than the abdomen. Length of the males, l.lJ""". 



Female. — A little darker colored than the males ; antennae shorter, only 0.7""" long; 

 14 to 15 jointed, joints not pedicellcd ; ovipositor long, telci-copic, yellowish brown, 

 lighter towards the end; in other respects like the male. Length of the females, 

 1.6"™. 



Larva.— The larva is 1.5-2°"'"' long, light reddish yellow ; lives 2 to 4 together in the 

 pod-like folded leaflets of red clover (Trifolium pi-atmse L.), raid there undergoes its 

 transformations. 



Fupa. — The pupa is 1.2 to 1.5""" long, reddish brown; the forepart andwing-covera 

 dusky brown. It rests in a white silken cocoon, which it breaks through and leaves 



thread-like particles, which seemed to grow somewhat like crystal-needles; the larva 

 during this time remained perfectly motionless. The cocoon is perfected within a 

 few days, and even then, under a strong magnifying power, no thread is observable. 



Walsh (Proc. Ent. Soc. Phil a., 1864, "p. 560), referring to these views of Winnertz, 

 says: "Iliilieva that it is in tliis manuor that the pupal cocoon of all Ceddomyia 

 is formed." Oston Sacken himself seems to have attempted no generalization upon 

 this point. 



