(/:> NEW YORK STATE MUSEUM 



generations in almost four years and presumably was capable of 

 continuing this much longer. The adults of Miastor and Oligarces 

 occur in midsummer, a season when the midges of most of these 

 forms are probably abroad. 



Biological observations. The first larvae secured wevt taken 

 October 5, 1910, placed in an ordinary fruit jar with moist sand 

 and subsequently allowed to become rather dry. A second lot was 

 obtained October 19 and on examining the latter November i8th, an 

 adherent mass of young larvae evidently recently escaped from the 

 mother larva was found. Soft, partially rotten wood was taken 

 from the earlier lot presumed to contain little or nothing alive, and 

 one or tw^o of these young larvae placed in a groove in each piece 

 of wood, the latter being attached by light clamps, either directly 

 to a microscopic slide or held between a pair. These preparations 

 were kept in a closed tin box on damp blotting paper. It was hoped 

 that we would be able to watch the development of the one or more 

 larvae thus placed in each piece of wood. Most of these for some 

 reason or other escaped and we soon found that the additional 

 moisture given these pieces resulted in renewed activities on the 

 part of many larvae concealed in the woody tissues. On Novem- 

 ber 28, ten days after these preparations had been made, numerous 

 young larvae were observed in most of the preparations, the ma- 

 jority probably recent young of larvae stirred to renewed ac- 

 tivity by the addition of moisture. Throughout November and in 

 early December large, white mother larvae capable of producing 

 from five to perhaps fifteen embryos were frequently seen. The 

 latter part of December and during January large, white larvae 

 were difficult to find and the major portion of the reproduction was 

 by the small, yellow mother larvae usually occurring in crevices in 

 the sapwood and producing only one or two young. These prepara- 

 tions afford an excellent opportunity for determining the duration 

 of the quiescent period under nearly natural conditions. This was 

 found, as a result of observations upon a number of larvae, to be 

 in the vicinity of a week, the movements of the embryo with the 

 fuscous ocular spot and brown anterior portion of the head being 

 observable about five days prior to the escape of the young. The 

 occurrence of a small amount of mold did not seem to have a 

 material effect upon the health of the larvae, and the same was 

 true respecting the presence of mites, Tyroglyphus, which were 

 upon occasions rather abundant in some of the preparations. The 

 larvae crawl readily between the glass and the wood, occasionally 



