54 



than curculios, this order of things was reversed a little later in the year. Some per- 

 sons will no doubt wonder how suoh a large fly can be developed from a curculio larva 

 which is stung while so young ; but we do not know how long the parasite egg remains 

 unhatched, and it must be remembered 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 destroy its prey by attacking 

 those parts more vital. 



" This parasite, which I will now proceed to describe, belongs to the second sub- 

 family {Braconkles) of the Ichneumon flies (IchiKumonkla;), and the venation of its wings, 

 and the three-jointed abdomen, place it in the genus Siyalphus. Westwood (Synopsis, 

 p. 63), gives three cubital panes or areolets in the front wings as characteristic of the, 

 genus ; but Brul6 (p. 510) and, as Mr. Cresson informs me, Westmael in his Braconides de 

 Belgique, give only two, which is the number in our insect. 



" Sigalp}m& curculionis, Fitch — Imago (Fig. 15 a, male ; b, female). Head, black, sub- 

 polished and sparsely covered on the face with short whitish hairs ; oceDi touching each 

 other ; labrum and jaws brown ; palpi pale yellow ; antennae (Fig. 15 c) twenty-seven- 

 jointed, filiform, reaching when turned back, to middle joint of abdomen or beyond, the 

 iDulbous and small second joint rufus and glabrous, the rest black or dark brown, though 

 3-10 in many specimens are more or less tinged with rufous; 3-14 very gradually dimin- 

 ishing in size ; 14-27 sub-equal. Thorax, black, polished, the metathorax distinctly and 

 broadly punctate, and the rest more or less punctate or rugose, with the sides sparsely 

 pubescent. Ahdmnen, pitchy-black, flattened, the dorsum convex, the venter concave, 

 and the sides narrow-edged and slightly carinated ; the three joints distinctly separated 

 and of alwut equal length ; the first joint having two dorsal longitudinal carina; down the 

 middle ; all densely marked with very fine longitudinally impressed Unes, 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 abdomen, 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; and tarsi, and sometimes the hind 

 femora, dusky. Wings, sub-hyaline and iridescent, the veins pale rufous, and the stigma 

 black. Length, female .15-. 16 inch, expanse, .30 ; male differs only in his somewhat 

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

 eyes are more or less distinctly rufous. 



"Described from 50 females, and 10 males, bred June 23rd — July 29th, 1870 ; from 

 larvas of Conotrachelus nenuphar, and 2 females obtained from Dr. Fitch." 



"Larva (Fig. 14a), white, with translucent yellowish mottliiigs. Pupa (F'\g. 14 c, 

 female), .17th inch long, whitish, members all distinct, the antennaB touching hind tarsi, 

 the ovipositor curved round behind, reaching and touching with its tip the third abdom- 

 inal 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. 

 14 h), composed of one layer of closely woven yellowish silk." 



" Variety Pm/us. — Head, thorax and most of the first abdominal joints entirely 

 rufous, with the middle and hind tibia; dusky, and the ovipositor three times as long as 

 abdomen, and projecting more than twice the length of the same beyond its tip. Des- 

 cribed from three females 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 

 correspondence in all the sculpturing of the thorax and body, and in the venation of the- 

 wings, it might be considered distinct. The greater ItMigth of the ovipositor is very char 

 acteristic, and accompanies the other variation in all three of the specimens." 



