PACKARD. 1 THE SWEET-POTATO HELMET-BEETLE. 739 



in jjardens ; and at the close of tbe year 1845, many of them were sent 

 to me as abounding on decayed portions of planted potatoes, and 1 have 

 met with them likewise about the tubers and in flower pots, where they 

 burrow in all directions. Some I received in July were about ^ of an 

 inch lonf?, of an ochreous-brown or snuflf color, and shagreened ; the 

 back is slightly convex, with twelve well-detined wrinkled segments, 

 and a horny, shining head, much narrower than the body, intensely 

 black or inclining to chestnut color, and slighty hairy ; there are eight 

 distinct spiracles on each side, the penultimate segment is rounded, 

 with four teeth on the margin, and the anal one has four smaller teeth, 

 with two large spiracles near the base ; it has no feet. 



"They were transformed to pupae in the earth in the beginning of 

 August, and were then yellowish-white; the thoracic portion was very 

 thick, with two horns in front ; the body slender and subcylindric, the 

 segments very distinct, with spiracles down the sides, and the tail spiny. 



"The flies hatched on the 21st of August, but they abound in fields, 

 hedges, especially under trees, and even in the highways around Lon- 

 don, the whole of that month; and there must be two broods of them, as 

 they are found likewise in May. They belong to the fauiily Tipulid^, 

 and to the genus Dilojjhus. The species was named febriUs by Lin- 

 naeus, from the generally-received opinions in Sweden of these flies 

 resorting to houses where intermittent fevers existed. 



" D. febrilis is intensely black, shiniujij, and hairy. The head of the male is hemis- 

 pheric, and covered with large densely pubescent eyes of a reddish-brown color. There 

 are three minute ocelli forming a.) elevated triangle near the base ; the tip is broad, 

 and the feelers incurved ; the trunk is oval and gibbose, with two transverse rows of 

 minute teeth before; the scutel is short and broad ; abdomen sublinear, eight-jointed, 

 the apex, clubbed ; the two wings are incumbent in repose, perfectly transparent and 

 white but iridescent, the pinion only is slightly tinged with brown, the costal nervures 

 pitchy, the others very faintly marked ; a radial nervure uniting with the costa at the 

 tuiddle forms a brown spot at the extremity; two balancers, with a large compressed 

 brown club ; it has six long legs ; anterior thighs the thickest, the shanks very short, 

 the apex surrounded by a coronet of teeth. There are also several short spines outside ; 

 feet slender, five-jointed, terminated by claws and suckers; length, 2^ lines ; expanse, 

 5 lines. The female is larger and very difiereut, the head being much less, with small 

 oval eyes not meeting on the crown ; the abdomen is brownish and elongated, ovate at 

 the extremity but narrowed at tbe base, and the tip is furnished with two minute tuber- 

 cles; the wings are much longer and very ample, entirely brown, the pinion being the 

 darkest, with a brown stigniatic spot; all the nervures are pitchy; the anterior thighs 

 are iucrassated. 



"These insects fly heavily, their hinder legs hanging down, and in the 

 evening they become sluggish, resting on herbage and bushes. The 

 larvae also inhabit cow-dung and horse-muck ; it is therefore very possi- 

 ble they may be introduced into potato-grounds with the manure, or 

 the flies may be attracted to highly-manured ground to deposit their 

 eggs ; for so little is known of the economy of many insects, that it is 

 impossible to determine their exact habits ; indeed, no description or 

 figures were to be found of the larvae and pupae of this fly until 1 sent 

 them to the Gardener's Chronicle." 



INJURING THE SWEET-POTATO. 



The Helmet-Beetle, Coptoci/cla aurichalcea (Fabricius). — Feeding on the leaves; 

 broad, flattened, spiny grubs, holding their cast-ott' skins over their backs. 



This beetle, which usually feeds on the leaves of the morning-glory, 

 will sometimes destroy whole fields of sweet-i)Qtatoes, and is specially 

 injurious to plants trausf rred from hot-houses. 



The larva is broad and flat, with a row of large, long, barbed, spines 

 along the edge of tjie body, sixteen on each side, the two posterior of 



