THE AMERICAN ENTOi^[OLOGIST. 



150 



spot ccjiial to tlie head in size; and there are six 

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

 oral appearance it somewhat resembles the larva 

 of the Ciicunibcr-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.oo of an inch, and breadth O.OtJ of an 

 inch. It feeds upon roots beneath the ground. 



•■The pupa (Fig. Hi) 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 see that on June 14, l(<().i, 

 I put a number of the larvie into a breeding-box 

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

 some of the larvie had disappeared beneath the 

 ground. July f , I found in the box the beetle. 

 This gives us seventeen days from the time the 

 larva entered the ground, having ceased eating, 

 until I obtained the perfect insect. I did not 

 open tlic breeding-box every day, but as the in- 

 sect was yet (jnilo pale and soft, conclnde that 

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

 ground. The actual time, however, in the 

 pupa state, was less than seventeen days, for, 

 like the larva of the Cucnmber-beetle and other 

 lieetles, these worms pass a kind of intermediate 

 state, in a quiet, motionless condition, in their 

 little dirt-tombs beneath the ground. During 

 tliis time they decrease in length very much, 

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

 riod is a peculiar part of the larval state, and 

 nuiy be called the quiescent or 'shortening pe- 

 riod,' in contrast with the feeding period. At 

 the end of this preparatory, shortening period, 

 tlie little larva casts its skin and becomes a pupa. 



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

 ber of these 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 shart, onlv a lew 

 days. 



"Every gardener knows that these insects 

 are very injurious to young cabbages and tur- 

 nips as soon as they appear above tlie 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 

 tlie stem is so hard that the insect will not 

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

 n-nally to bo injured by them. But if we would 



gain much true knowledge of what is going on 

 around us, even among these most sinii>lo and 

 common things, we must learii to observe inoro 

 closely than most men do. 



" Tlic 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 find them eaten away by 

 some insect, and by searching closely about the 

 roots will find the larva, grub, worm, or what- 

 ever else he may choose to call it ; from tliis ho 

 can breed the Striped Tnrnip-boollo. as 1 have 

 often done. 



''I have observed the depredations of these 

 larv* for ten years, and most of that time had 

 a coiivincing knowledge of theirorigin. but only 

 proved it in 1865; since that tinio 1 liavo made 

 yearly verifications of this fact. 



•' Every year the young cabbage plants and 

 turnips in this region receive great damage from 

 these larvae, and oft&u when we have dry 

 weather, in the latter part of May and early in 

 .Tune, the cabbage plants are ruined. A large 

 proportion of the plants arc killed outright in 

 June, and the balance rendered scarcely tit for 

 planting; but when the ground is wet to the 

 surface all the time by freciuent rains, the 

 young plant is able to defend itself much more 

 etl'ectually, 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 those 

 surface roots find no nourishment and tlio 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 yonng 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 the 

 roots of the Cruciferous (nmstard) family. 



[25^ As some of our exchanges may wish to 

 illustrate any article they may copy from the 

 Amkuicax Entomologist, we have decided to 

 furnish electrotypes of our wood cuts, at ono- 

 half the cost of engraving; these electrotypes to 

 be retained by the parties receiving them, it' 

 tliey desire it. 



