206 NEW YORK STATE MUSEUM 



191 1 Can. Ent., 43:i34~35; same in Science, 33:538; Econ. 



Ent. Jour., 3:296; Ent. News, 22:227; N. Y. Ent. Soc. Jour., 19:200-1 



191 1 N. Y. State Mus. Bui. 147, p. 82-104 



1911 Econ. Ent. Jour., 4:414 



191 1 Wheeler, W. M. N. Y. Ent. Soc. Jour., 19:201 



Prior to 1910 this species was known only through one female 

 taken at Highland June 18, 1907. The interesting larvae of this 

 remarkable form have subsequently been found in the decaying bark 

 of maple, chestnut, oak, birch, beech and hickory at Highland, 

 Tivoli, Nassau and Lake Placid, N. Y., indicating a considerable 

 range for this species. The writer's experience justifies the belief 

 that these insects are rather common under bark, in the incipient 

 stages of decay. Miastor larvae have also been found in Con- 

 necticut and Indiana. A variable number of pedogenetic gen- 

 erations may occur in the fall and spring, the appearance of the 

 adult midges being presaged by the development of a breast- 

 bone in the larvae, the formation of a prepupa and pupation. An 

 extended discussion of pedogenesis as observed in this species, ac- 

 companied by descriptions of the larva and female, may be found in 

 the writer's report for 19 10. Stages not previously characterized 

 are described below. 



Prepupa. (PI. 14, fig. i) Length 1.75 mm. This stage is easily 

 recognized by the apparent contraction and withdrawal of the 

 body contents from the two extremities. The second to fifth seg- 

 ments become greatly enlarged, semitransparent, and on examina- 

 tion under a high power may be seen to contain the developing 

 thoracic segments and their appendages. The head is much less 

 prominent, being partially withdrawn into the anterior body seg- 

 ments. The well-developed breastbone is frequently visible, though 

 occasionally obscured and is shed with the prepupal exuvium. The 

 posterior extremity is also semitransparent and in the male distinctly 

 bilobed. 



Pupa. Length 1.5 mm; anterior extremity broadly rounded, 

 semitransparent, the thoracic region somewhat larger, the thoracic 

 horns long,, slender, curved, the abdomen gradually tapering to a 

 rather obtusely rounded, bilobed extremity. The posterior portion 

 of the thoracic region and most of the abdomen whitish, the latter 

 with a distinct orans^e tint in the subapical segment ; terminal seg- 

 ment somewhat swollen, semitransparent, bilobed. Antennal, wing 

 and leg cases semitransparent, the two latter extending to about the 

 second abdominal segment and all, together with the eyes, gradually 

 becoming infuscated till nearly black just prior to the appearance 

 of the imago. The female pupa may have a length of 2 mm, the 

 abdomen being longer, slender, and when viewed by transmitted 

 light may show 4 or 5 large eggs. 



