ARTHUR DEWITT WHEDOX 377 



Avell preserved in strong alcohol and later transferred to 83 per 

 cent alcohol. 



The specimens from the Philadeli)hia district and those ob- 

 tained from Dr. Calvert were prepared in various ways: some 

 were killed by dropping for a moment into boiling water, opening 

 and transferring to 83 per cent alcohol. These turned out very 

 well on dissection; others were killed in warm Gilson's Fluid (Wil- 

 liamson, 1916), washed in running water,- and preserved in 83 

 per cent alcohol, ^'arying periods from twenty minutes to sev- 

 eral hours in the Gilson's Fluid were tried. The best results 

 came with shorter or medium time of treatment. Those in longer 

 seem ill preserved and clogged with crystals. 



For the staining of parts or dissections Grenacher's Borax 

 Carmine, after some experiment, was selected. A treatment 

 varying from twenty minutes to two hours depending upon the 

 size and nature of the specimen gave better results than the 

 much longer treatment usually recommended. Cedai' oil and 

 (Jil of Bergamot were used with equal success in clearing. Where 

 permanent mounts were desired clear thick Canada Balsam was 

 used, and in the case of thick specimens bits of object slides were 

 placed as supports beneath the cover. It was, however, often 

 advantageous to dissect stained material while it was immersed 

 in the clearing fluid. 



When the season permitted, the best results were obtained by 

 keeping living specimens in papers or cages until the digestive 

 tract was well emptied, then decapitating, splitting the body 

 with fine sharp scissors along the desired lines, and pinning out 

 to harden in a small wax-lined dissecting pan (an ointment box 

 three oi- four inches in diameter) containing 70 per cent alcohol. 

 Aftei- a half hour 83 per cent alcohol was applied and the speci- 

 men allowed to remain about an hour longer. It could then be 

 taken uj) and placed with the proper labels in a pill vial in the 

 same stiength of alcohol. Gilson's mixture was used in the same 

 way but seemed to have no advantages either in preserving the 

 tissues or jireparing for the stain. There is no doubt that for 

 anatomical studies of insects the dissection of freshly killed 

 material yields the most dependable results, but the information 

 thus obtained is doubly certain when checked up by a siniul- 



TRAXS. AM. ENT. SOC, XLIV. 



