24 



THE ALDER FLEA-BEETLE. 



(Haltica alni Harris.) 



In the correspondence of the late Dr. Harris the following mention is 

 made of this beetle : " In traveling from Centre Harbor, N. H., to Con- 

 way, on the 2d of August, 1854, and from Conway to Upper Bartlett, 

 and subsequently to Jackson, we saw the Alders (Alnus serrulata) every- 

 where ravaged by insects which had destroyed their leaves in the man- 

 ner of canker worms. Upon examination the spoilers were found not 

 to be all dispersed and several were seen upon the leaves still continu- 

 ing their work $ at the same time were found in Conway numerous 

 beetles, which proved to be a species of Haltica, eating the leaves off 

 the same Alders. The larva3 which had ravaged the shrubs were doubt- 

 less those of the Haltica before named." 



We have reared the beetles from the grubs during the past season. 

 At Merepoint, near Brunswick, Me., during the middle of August, 

 1886, we noticed clumps of Alders standing in dry soil partly defoliated 

 or with skeletonized, brown or blackish leaves, on which, as well as 

 the still remaining green leaves, were black grubs, sometimes seven or 

 eight on a leaf. All the alders in the region were not molested, the 

 grubs occurring locally. August 15 we found a single beetle, on 

 placing a number of leaves with the grubs in a tin box. We found a 

 white pupa lying loosely on the bottom of the box August 20 ; soon 

 more pupae appeared, and the beetles began to appear in considerable 

 numbers the last week of August. It is evident that in nature the 

 larva falls to the ground to transform, the pupae entering the earth. 



Afterwards, September 10, we found whole clumps of Alders at the 

 base of Iron Mountain, Jackson, N. H., stripped by the grubs, nearly all 

 the riddled, brown, dead leaves having fallen off and thickly covering 

 the ground under the bushes. Such a wholesale devastation of Alders 

 we never witnessed. By this time the beetles had become very abun- 

 dant, and were apparently feeding on the few leaves still attached to 

 the tree. The Alder is the source of some of our destructive forest and 

 fruit insects, and should this grub ever spread to other food trees it 

 will be very annoying, though it can be subdued by proper spraying. 

 There seems to be a periodicity in the appearance of this beetle in 

 unusual numbers, Harris having seen the same grubs in great abun- 

 dance in 1854 in the same region. We have never observed iz so com- 

 mon and destructive before in Maine. It is most probable that the 

 beetles hibernate under the leaves and, soon after the leaves expand 

 in May, lay their eggs in masses on them, the grubs scarcely stirring 

 from the leaf on which they are born, until ready to pupate. The 

 grubs are probably distasteful to birds, otherwise they would fall an 

 easy prey to them and be kept within due limits. 



Descriptive. — Larva. — Body somewhat flattened ; head scarcely two-thirds as- 

 wide as the body in the middle; black, becoming brown in front near the jaws. 

 Body livid brown above; the tubercles black; paler beneath; with three pairs of 



