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NEW YORK STATE MUSEUM 



dead leaves and rubbish may be put in the glass for them to 

 f e( d ni)ou. The larvae of C h i r o u o m u s usually hide them- 

 selves from view, and in the mud and debris form tubes which 

 open at the surface. When placed in a jar their chief anxiety 

 is to bury themselves in the mud, and very soon they will gather 

 bits of dead leaves and particles of sand about them, binding 

 them together Avith viscid threads passed out of the mouth, and in 

 a short time will be completely concealed in a rough tube. These 

 tubes are frequently seen upon the surface of dead leaves, on 

 stones, sticks, etc. One species is known to be a leaf miner 

 (Pettit, 1900). The larvae of species belonging to the groups 

 Oeratopogon and T a n y pus usually do not form tubes, 

 but remain free. Specimens captured in the fall may live all 

 winter and not transform until spring. Some specimens of 

 Oeratopogon taken by the writer in September lived until 

 the following May in the larval stage, and it is probable that 

 they live thus nearly a year. The larvae may be found all the 

 year around, while the adults are common excepting in the dead 

 of winter, and a few specimens may be found even at that season. 

 The larvae are best preserved in alcohol, either first killing 

 them in hot water, or placing directly in the alcohol. If any 

 peculiarity of color marking is observed it should first be noted, 

 as the s])irits soon remove much of the pigment. The adult should 

 be mounted with great care, either upon an elbow pin (^lacGil- 

 livray, 1903b), or upon a minuticn nadel, a short and very 

 slender headless pin, thrust through a small piece of cork or 

 pith and then into the under side of the thorax of the fly. 

 Through the other end of the cork an ordinary insect pin is 

 placed, and the specimen is then ready for the cabinet. It is 

 also veiy desirable to preserve some specimens of each species 

 in alcohol, or better still, in a mixture of formaldehyde and 

 glycerine. The latter preserves the original colors quite well, 

 especially if kc]it in the dark. These specimens should be put 

 in very snmll vials and should, of course, bear the same number 

 label as the pinned specimen. The fore tarsi of the genus 

 C h i r o n o m n s are very easily broken oflf, and therefore it is 

 quite necessary that great care should be observed in preserving 

 them since their presence is necessary in Jlie determination of 



