TACKAKD.] 



THE HAIRY POTATO-MAGGOT. 



733 



single egg in an oblong slit in the stalk about one-eighth of an inch long, 

 which she has previously formed with her beak in the stalk of the potato. 

 The grub afterward hatches and bores into the heart of the stalk, work- 

 ing downward toward the root, causing the stalk to wilt. When ob- 

 served to suddenly die the stalks should be cut down and burned. 



Beetle. — Bluish or ash-gray, with three shining, black, impressed spots at the lower 

 edge of the thorax. The grub (larva) when fully grown is a little over one-fourth of 

 an inch long, and is soft, whitish, footless, with a scaly head. — (Riley.) 



Besides these insects the "potato- worm," or caterpillar of the five- 

 spotted hawk-moth, and the caterpillar of the Gortxjna nitela, which 

 bores in "corn, and the helmet-beetle {Co2)tocyda miHchaJcea), which 

 usually feeds on the sweet-potato and nioruiug-glory, occasionally prey 

 on the potato-leaves. 



The clubbed tortoise-beetle {Deloycda clarata) was found in 1871 by 

 Mr. A. G. Smith, of Berlin, Mass., to be feeding on the leaves of the 

 potato, " eating indilierently different varieties." 



The Hairy Fotxto-Maggot, Eomalomy'ta iuherosa Cnrtis'? (Fig. 13.)— Feeding in 

 decaying (?) potatoes and cabbages ; a flat, hairy maggot, which transforms to a fly 

 like the common house-fly, but paler and smaller. 



A few years ago specimens of a hairy 

 maggot taken by Mr. C. A. Putnam Au- 

 gust 15, 1875, in defective potatoes, were 

 sent to the museum of the Peabody Acad- 

 emj^ofScience, at Salem, Mass., and shortly 

 after the museum received a number of 

 maggots of the same species found, July 

 2, 1875, in the Savoy cabbage, by Mr. John 

 H. Sears, of Danvers, Mass. The latter 

 lot consisted of two broods, i. e., of maggots 

 fully grown, and others one-quarter grown. 

 They are very similar, if not identical, with 

 Curtis's Homalomyia iuberosa. Our species 

 is probably the one referred by Harris to 

 the Anthomyia canicnilaris of Europe, and 

 is perhaps, as suggested by Baron Osten 

 Sacken, H. scalar is. 



Fig. 13. — Hairy potato-maggot 

 (Homalomyia tuherosai) a, larva; 

 &,the same enlarged twice. After 

 Curtis. 



Description of the larva (Fig. 13: rt, natural size; i, magnified twice). — Head minute, 

 fleshy, not seen in the pupa-case. Body flattened, cylindrical, ovate. Prothoracic seg- 

 ment flat, square, trapezoidal. On the body are two rows of long, slender dorsal spines 

 or hairs, two rows of lateral longer hairs (seen under a high magnifying power to have 

 short spiracles), one subdorsal, the other subvential. The last four dorsal are longer 

 than those in front. The end of the body forms a flat, smooth declivity, on each side 

 of the front edge of which is a thick, stout, short spine (a produced spiracle), much 

 thicker than the others, and ending suddenly in four short, blunt spines. Behind these 

 two spines, on the side of the declivity, are six hairs, with short, slender respiratory 

 hairs ou the basal half. Some of the lateral hairs have similar lateral respiratory fila- 

 ments, but they are less distinct than ou the six terminal hairs. The underside of the 

 body is flattened. The spiracles at the base, on each edge of the first segment behind 

 the head, have six long, slender respiratory processes. Length, 0.27 inch. This descrip- 

 tion will also apply to the pupa-case. 



It is easy to see how maggots like these, which bury themselves in 

 cabbages and potatoes, may become swallowed with the food, and if 

 the latter is only partially cooked and hastily swallowed, how the living 

 worms become conveyed into the stomach, and become so annoying that 

 the doctor has to be sent for. The European Homalomyia scalaris, or 

 " ladder-maggot," is not unfrequeutly voided from the bowels of boys 

 and adults in both countries. 



