1864.] 569 



the cocoon being spun. Having once become firmly possessed by this 

 notion, he implicitly accepts and adopts the statement of a lady, that 

 she saw " many of the maggots [of the wheat-midge] in the very act 

 of emerging from their skins" [cocoons], and makes confusion worse 

 confounded, by maintaining that the larva of that insect first of all con- 

 structs a house for itself by sloughing off its entire " skin " like the 

 Hessian Fly, and then, unlike the Hessian Fly, crawls out of that house 

 and goes underground naked to transform to pupa ! (Ibid. pp. 595 — 8.^ 

 It must have been, not the maggot (larva), but the papa, that the lady 

 saw emerging in the summer from what she called its " skin," but what 

 is in reality its cocoon, thin and filmy indeed, but no more so than those 

 of the Willow Gall-gnats, and enveloping the larva closely as in C. s. 

 brassicoides. (Marsh, and Kby.) And the " silvery coverings glisten- 

 ing in the sunshine on the ears of the wheat" so graphically described 

 by the same lady, (ibid. p. 597,) are manifestly not the '' skins," as Har- 

 ris believed, of the larvae that had gone underground for the winter, 

 but the cocoons of the comparatively few individuals that remain through- 

 out in the ear of the wheat and transform to imago the same season ; as 

 observed by Marsham and Kirby, and as occurs in many insects belong- 

 ing to other Orders, e. g. the Canker-worm (Anisopteryx vernata Peck) 

 and Acronycta oblinita Guen. (Walsh, Trans. III. St. Ayr. Soc. IV. p. 

 358.) In scientific matters, to get at the truth from amidst the confused 

 and contradictory evidence of non-scientific observers, often requires 

 the abilities of a first-class Philadelphia lawyer. Harris, indeed, states, 

 as of his own knowledge, that " not the slightest vestige of the larva-skin 

 [cocoon] was found in the earth in which some of these insects had under- 

 gone their transformations," and that " the pupa is entirely naked." (Ibid. 

 pp. 597-8.) But this may be readily accounted for on the hypothesis, that 

 when the larva goes underground the excessively thin cocoon, being 

 glutinous when it is newly exuded and not drying rapidly in the moist 

 earth, adheres strongly and becomes indissolubly agglutinated to the 

 dense medium that surrounds it, as does the cocoon of C. s. batatas n. 

 sp. to the surrounding moist, dense, spongy matter of the gall of that 

 insect; whereas, when the same cocoon is exuded by the same larva 

 among the loose chaff" of the wheat-ear, it dries rapidly and is not so 

 agglutinated. It has been already stated that in C. s. cornu n. sp. and 

 C s. siliqua n. sp. ? part of the thin, filmy cocoon adheres strongly to 

 the surrounding medium and part does not. 



