Xylota. 509 



or spur below near the apex. The legs haired as usual, the hairs on 

 femora shorter or longer, sometimes rather short, especialiy on hind 

 feinora; the bristle above the trochanters more or less distinct, at all 

 events on the anterior legs. Glaws and pulvilli well developed ; em- 

 podium small, spine-shaped, slightly hairy. Wings somewhat long; 

 medial cross-vein more or less oblique, placed behind or almost on 

 the middle of the discai cell; the basal part of the radial vein with 

 fine, somewhat short bristles; no stigmatical cross-vein. Thoracai 

 squamula with long, branched hairs, stopping rather long before the 

 angulus, alar squamula with shorter, flat hairs. Plumula short with 

 simple hairs. 



The developmental stages are somewhat well known. Scholtz 

 (Ent. Zeitschr, Breslau, 4, 1850, 31) found quite immature specimens 

 of X. lenta numerous in a decaying Acer in the middle of May. West- 

 wood mentions briefly (Introd. II, 1840, 559) the puparia of X. pigra 

 and florum, the former probably from rotten wood. Perris describes 

 and figures (Ann. Soc. Ent. de Fr. 4, X, 1870, 326, PL 4, fig. 112-124) 

 the developmental stages of X. pigra ; the larvæ lived together with 

 larvæ of Mycetohia pallipes below the bark on Pinus among the detritus 

 and excrements from Tomicus sexdentatus (stenographus) and Acaniho- 

 cinus aedilis; the author says that the imago develops in spring from 

 larvæ from the foregoing autumn, and in summer and autumn from 

 larvæ which have developed in summer. Beling describes (Arch. f. 

 Naturg. 41. 1875, 54) larva and pupa of X. segnis; the larvæ were 

 found in a decaying, humid stub of a beech on ^/g, the imagines 

 developed next spring on ^^U and folio wing days; on the same place 

 the author found on ^k still many larvæ and only a few pupæ; the 

 imagines developed until ^'^Z« and among them were two specimens of 

 X. lenta, the larva of which thus had been together with the larva of 

 segnis. Verrall figures (Brit. Fl. V, 1909, 39, fig. 69) larva and pupa of 

 X sylvarum, but no notes are given. I have myself examined larva 

 and pupa of X. segnis and nemorum ; the larvæ of segnis were taken 

 in a decaying, humid stub of a beech on ^/s; those of nemorum were 

 taken in the same way on ^/e, they pupated about ^^/6 and developed 

 on ^^/e and the following days, another larva was taken in water in 

 a tree-stub on ^'^/t, it developed on ^''/t, and a pupa was taken in a 

 quite similar place on ^''/t, developing on -^^/t. — The larva of X. segnis 

 is elongated, arched above, a little flattened below; it is a little 

 attenuated at the head end, or, when not at all contracted, almost not 

 thinner at the anterior end; towards the posterior end it is more 

 attenuated ; the dermis is finely chagreened from small spines or hairs, 

 and the body is transversely corrugated ; the prothoracal segment has 



