THE AMERICAN ENTOMOLOGIST. 



159 



spot equal to the liead in size; and tliere are six 

 true legs and one proleg. In its form and gen- 

 eral appearance it somewhat resembles the larva 

 of the Cucumber-beetle, but it is much smaller. 

 Its motion is slow, arching up the abdomen 

 slightly, on paper or any smooth surface, in 

 such a position that its motions are necessarily 

 awkward and unnatural, because in a state of 

 nature it never crawls over the surface, but digs 

 and burrows among the roots in the ground. Its 

 length is O.;!o of an inch, and breadth O.OG of an 

 inch. It feeds upon roots beneath the ground. 



"The pupa (Fig. 11!» c) is naked, white, and 

 Iransforms in a little earthen cocoon, pressed 

 and prepared by the larva, in the ground near its 

 feeding place. This period is short. 



'' From my notes I sec that on June U, l>>(i."), 

 1 put a number of the larvie info a breeding-box 

 with a supi)ly of their natural food. June 17, 

 some of the larv;e had disappeared beneath the 

 ground. July 4, I found in (he box the beetle. 

 This gives us seventeen days from the time tlio 

 larva entered the ground, having ceased eating, 

 until I obtained the perfect insect. I did not 

 open the breeding-bo.x; every day, but as the in- 

 sect was yet quite pale and soft, conclude that 

 it was not more than a day or so out of tlic 

 ground. The actual time, however, in the 

 pupa state, was less tlian seventeen days, for, 

 like the larva of the Cucumber-beetle and other 

 liectles, these worms pass a kind of intermediate 

 slate, in a quiet, motionless condition, in their 

 little dirt-tombs beneath the ground. During 

 tills time they decrease in length very much, 

 becoming a shorter, thicker 'grub." This pe- 

 riod is a peculiar part of the larval state, and 

 may be called the quiescent or 'shortening pe- 

 riod,' in contrast with the feeding period. At 

 the end of this preparatory, shortening period, 

 the little larva casts its skin and becomes a pupa. 



•' During the past summer I bred a good num- 

 ber of tliese beetles from the larva and pupa, 

 taken from their breeding places beneath the 

 ground; but as I took no precise notes of the 

 date, I can say no more regarding the time of 

 the pupa state, except that it is s-hort, only a lew 

 days. 



"Every gardener knows that these insects 

 are very injurious to young cabbages and tur- 

 nips as soon as they appear above the ground, 

 by eating otf the seed-leaves; he also almost 

 universally imagines that when the second, 

 or true-plant leaves appear, then the young 

 plant is safe from their depredations: then 

 the stem is so hard that the insect will not 

 bite it, and the leaves grow out so rapidly as not 

 usually to be injured by them. But if we would 



gain much true knowledge of what is going on 

 around us, even among these most simple and 

 common things, we must learn to observe more 

 closely than most men do. 



" The gardener sees his young cabbage plants 

 growing well for a time, but at length they be- 

 come pale or sickly, wither and die in some dry 

 period that usually occurs about that time, and 

 attributes their death to the dry weather; but if 

 he will take the pains to examine the roots of 

 the plants, he will tind thein eaten away by 

 some insect, and by searching closeh' about the 

 roots will tind the larva, grnb, worm, or what- 

 ever else he may choose to call it; from this he 

 can breed the Striped Turnip-beetle, as 1 have 

 often done. 



''I have observed the depredations of these 

 larva; for ten years, and most of that time had 

 a convincingknowledge of theirorigin, but only 

 proved it in 18(io; since that time I have made 

 yearly verilications of this fact. 



'■ Every year the young cabbage plants and 

 turnips in this region receive great danujge from 

 these larvie, and often when we have diy 

 weather, in the latter part of May and early in 

 June, the cabbage plants are ruined. A largo 

 projiortion of the plants are killed outright in 

 June, and the balance rendered scarcely fit for 

 planting; but when the ground is wet to the 

 surface all the time by freipient rains, the 

 young plant is able to defend itself much more 

 eflectindly, by throwing out roots at the surface 

 of the ground, when the main or centre root is 

 devoured by the larva ; but in dry weather these 

 surface roots find no nourishment and the plant 

 must perish. 



"This year I saw these beetles most numer- 

 ous in early spring, but have often seen them in 

 August and September, so abundant on cab- 

 bages, that the leaves were eaten full of holes, 

 and all speckled from their presence, hundreds 

 often being on a leaf; and at.this time the entire 

 turnip crop is sometimes destroyed by them, 

 and seldom a year passes without their doing 

 great injury."' »****>.■ 



As the Cucumber-beetle exclusively raises 

 its young on the roots of the Cucurbitaceous 

 (gourd) family, so from these observations I 

 am led to believe from analogy, that the Striped 

 Turnip-beetle raises its young always on llu; 

 roots of the Cruciferous (mustard) family. 



E::^ As some of our exchanges may wish to 

 illustrate any article they may copy from the 

 American Entomologist, we have decided to 

 furnish electrotypes of our wood cuts, at one- 

 half the cost of engraving; these electrotypes to 

 be retained by the parties receiving them, if 

 they desire it. 



