128 Rev. T. A. Marshall's monograph of 



Wesmael and Rnthe (the latter doubtfully) considered 

 them distinct. It is hard to settle the question even by 

 breeding, for individuals of the same brood are always 

 uniform, while one brood is found to differ slightly from 

 another. It is probable that they all belong to one 

 inconstant species, the leading characters of which are 

 the absence of tracheal grooves, the tendency of the 1st 

 abdominal segment to become smooth, and the habit of 

 gregarious parasitism. 



Described from thirteen females, three males. The 

 form known as rubens occurs, according to Haliday, on 

 sandy coasts ; I have obtained it at Sandwich, and 

 among the roots of rushes at Freshwater Bay, Pembroke- 

 shire, where it was very abundant. But it is equally 

 common at a distance from the sea. Bignell bred two 

 broods from Agrotis tritici, L., gregariously, like Micro- 

 gasters. Their cocoons are irregularly heaped together, 

 and not pensile. The individuals of one batch are 

 larger than those of the other ; the latter came out 

 May 31st, to the number of thirteen, and continued in 

 the pupa-state eighteen days. 



31. Meteor us fragilis, Wesm. 



Perilitus fragilis, Wesm., Nouv. Mem. Ac. Brux., 1835, 



p. 52, i ? . 

 Meteorus colon, Hal., Ent. Mag., iii., 30, 2 . 

 M. fragilis, Ruthe, Berl. ent. Zeits., 1862, p. 55, $ ? . 

 Perilitus fasciatus, Batz., Ichn. d. Forst., i., 77, pi. vii., 



f. 15, ? . 



Black above, beneath navo-testaceons ; face, mouth, orbits, 2d 

 abdominal segment, in the $ also the apex of the abdomen, and 

 legs, pale ; 2d abdominal segment with 2 indeterminate black 

 spots ; scutellum sometimes rufescent. Antennae fuscous, except 

 the extreme base, long and slender, like the petiole and legs. 

 Wings ample, hyaline ; squanmLi' and stigma flavo-testaceous ; 

 nervures fuscescent ; recurrent nervine evected into the 2d cubital 

 areolet, which is prolonged for its reception, and is also much 

 narrowed towards the radius. Tracheal grooves obsolete. Terebra 

 about \ the abdomen. $ ? . Length, 2—2} ; wings, 4— 4A lin. 



Head not narrower than the thorax. Palpi whitish. Antenna' 

 setaceous, fuscous, or fusco-testaceous, becoming darker after flic 

 base; those of the ? longer than the body, 31 — o2-joiuted; ol the 



