THE STATE ENTOMOLOGIST. 27 



membered that it is a rule, wisely ordained and long known to exist 

 in insect life, that the parasitic larva does not at first kill outright, 

 but subsists, without retarding growth, upon the fatty portions of its 

 victim, until its own growth is attained. Thus the first worm derives 

 its nourishment from the juicy fruit, and grows on regardless of the 

 parasite which is consuming its adipose substance, until the latter is 

 sufficiently developed, and the appointed time arrives for it to de- 

 stroy its prey by attacking those parts more vital. 



This parasite, which I will now proceed to describe, belongs to 

 the second sub-family {Braconid.es) of the Ichneumon-flies (Ichneu- 

 monidce), and the venation of its wings, and 3-jointed abdomen, place 

 it in the genus Sigalphus. Westwood (Synopsis, p. 63) gives three 

 cubital panes or areolets in the front wings as characteristic of the 

 genus ; but Brulle (p. 510) and, as Mr. Cresson informs me, Westmael 

 in his Braconides de Belgique, give only two, which is the number in 

 our insect. 



Sigalphus curculionis, Fitch — Imago— (Fig. 7, a male ; b female). Head black, sub-polished 

 and sparsely covered on the face with short whitish hairs ; ocelli touching each other ; labrum 

 and jaws brown ; palpi pale yellow ; antenna* (Fig. 7, c) 27-jointed, filiform, reaching, when turned 

 back, to middle joint of abdomen or beyond, the bulbus and small second joint rufous and gla- 

 brous, the rest black or dark brown, though 3-10 in many specimens are more or less tinged with 

 rufous 5 3-14 very gradually diminishing in size ; 14-27 sub-equal. Thorax black, polished, the 

 metathorax distinctly and broadly punctate, and the rest more or less distinctly punctate or 

 rugose, with the sides sparsely pubescent. Abdomen pitchy-black, flattened, the dorsum convex, 

 the venter concave, and the sides narrow-edged and slightly carinated ; the three joints distinctly 

 separated and of about equal length ; the first joint having two dorsal longitudinal carinas down 

 the middle; all densely marked with very fine longitudinally impressed lines, and sparsely pubescent; 

 (Dr. Fitch in his description published in the Country Gentleman, under date of September, 1859, 

 states that these lines leave " a smooth stripe along the middle of its second segment and a large 

 smooth space on the base of the third ;" which is true of a few specimens, but not of the majority, 

 in which the impressed lines generally cover the whole abdomen.) Ovipositor longer than abdo- 

 men, but when stretched in a line with it, projecting backwards about the same length beyond ; 

 rufous, with the sheaths black. Legs pale rufous, with the upper part of hind tibia? aud tarsi, and 

 sometimes the hind femora, dusky. Wings subhyaline and iridescent, the veins pale rufous, and 

 the stigma black. Length 2, 0.15-0.16 inch, expanse 0.30; tf differs only in his some- 

 what smaller size and in lacking the ovipositor. In many specimens the mesothorax and the eyes 

 are more or less distinctly rufous. 



Described from 50 £ <J>, 10 tftf, bred June 23d-July 29th, 1870, from larvae of Conotrachelus 

 nenuphar, and 2 $ J obtained from Dr. Fitch. 



Larva (Fig. 8, a) — White, with translucent yellowish mottlings. 



Pupa (Fig. 8, c 5) — 0.17, inch long; whitish, the members all distinct, the antennas touch- 

 ing hind tarsi, the ovipositor curved round behind, reaching and touching with its tip the 

 third abdominal joint, which afterwards forms the apical joint of imago; five ventral joints, 

 which in the imago become much absorbed and hidden, being strongly developed. 



Cocoon (Fig. c, b) — Composed of one layer of closely woven yellowish silk. 



Variety hufos — Head, thorax and most of first abdominal joint entirely rufous, with the 

 middle and hind tibiae dusky, and the ovipositor three times as long as abdomen and projecting 

 more than twice the length of the same beyond its tip. 



Described from three $ £ bred promiscuously with the others. This variety is slightly 

 larger and differs so remarkably from the normal form that, were it not for the absolute corres- 

 pondence in all the sculpturing of the thorax and body, and in the venation of the wings, it might 

 be considered distinct. The greater length of the ovipositor is very characteristic, and accompa- 

 nies the other variation in all three of the specimens. 



