758 REPORT UNITED STATES GEOLOGICAL SURVEY. 



and nibble the ferns and make considerable bavoc among the plants 

 before its presence is suspected. 



Ou July IG I found one in a thin silken semi-transparent cocoon at- 

 tached to a leaf of Lathyrus maritimus ; the cocoon was large and full, 

 being nearly- half an inch long, cylindrical, both ends being rounded 

 alike. 



Description. — This iusect (Fig. 29, enlarged) is pitchy brown, 

 and covered with microscopic, pale scales, resembling a scallop- 

 shell, being marked with a few prominent ribs. Indeed, many 

 of the weevils seem to be provided with scales like those 

 of butterflies, Poduras, and a few other insects. The beak, 

 so short and slender in the radish-weevil, is here broad and 

 short, square at the end, from which the elbowed reddish-browu 

 antennae arise. The head is a little darker than the rest of the 

 body, and is coarsely punctured. The prothorax is coarsely gran- 

 ulated, the granulations being arranged iu irregular rows. The 

 wing-covers are adorned with about eleven high, rounded, longi- 

 tudinal ridges on each cover, and with coarse punctures along the 

 furrows between them. There are also about twenty rows of pale 

 dots along the wing-covers, consisting of scales. The legs, includ- 

 iug the claws, are rather paler than the rest of the body. The body 

 Fig. 29. Pitchy- is also covered with scattered pale hairs bent down on the surface, 

 Legged Weevil, especially on the top of the head; these hairs remain after the 

 enlarged. scales are rubbed off. It is a quarter of an inch in length, 



Wire-Worms and Cut-Worms. — Larvje of various snapping-beetles^ 

 Elater, Agrotis, etc. — Although these insects have been fully described 

 among those preying on wheat, corn, and grass, they are very destruc- 

 tive to young cabbages and allied garden -plants. Wire- worms feed on 

 the roots, and sometimes destroy the whole crop in Kentucky. In En- 

 gland wire-worms are destroyed for many successive years by sowing 

 salt over the surface of the ground at the rate of six bushels per acre 

 just as the small grain is coming up. 



Cut-worms are more difficult to contend with than wire-worms. They 

 are active at night, hiding by day in the soil around the roots of the 

 plants they infest. It would be well, therefore, to examine the soil 

 around the j'oung cabbage-plants, or to inclose the plants in tubes of 

 stout paper to prevent the attacks of the worm. 



As a remedy for wire-worms, J. H. Charnock, of Canada, advised the 

 use of rape-cake. " The remedy consists," says Mr. Eiley, "in applying 

 3 cwt. per acre of rape-cake broken into small lumps, and not crushed 

 into dust. It is spread on the land and plowed in before sowing the 

 seed. The worms are said to be so fond of it that they leave all other 

 kinds of food, while the cake is said to act upon them as a vermifuge 

 and to kill them, as they are found in it afterward in all stages, ' from re- 

 pletion to death and decay.' Rape-cake is extensively used in England 

 as a fertilizer, and I have not the least doubt but that it attracts the 

 wire-worms, and may be used as a trap for this purpose like sliced pota- 

 toes, etc." 



Eiley questions whether it is so efficacious as has been claimed, but 

 considers that it " is, however, well worthy of further trial, for even if, 

 as 1 suspect, it does not kill, it has the advantage over the other sub- 

 stances to be strewn as traps and then collected, in that it at the same 

 time acts as a fertilizer. Where it can be safely done, rape-cake as well 

 as sliced potatoes, turnips, etc., that can be used as baits for these in- 

 sects, might be poisoned with Paris green, and the necessity of collecting 

 the worms to destroy them thus avoided. I know of nothing manufact- 

 ured in this country that has the character of rape-cake, or could take 

 its place." 



