^7 



9 days later, adults began emerging. The size variance in the six 

 groups of Fi adults was greater than the size variance among the six 

 original females. Microscopic comparisons of the flies, made with 

 reference to Aldrich (1916) and James (15^7), revealed that all 

 specimens belonged to the same genus and species, Saraophaga robusta 

 (Aldrich), syn. S. plinthopy ga (Wied.). 



The colony was easily established. Females began mating and larvi- 

 positing when 5 and 11 days old respectively. Immatures were maintained 

 as described above and adults were maintained on fish meal and cane 

 sugar cubes. 

 Dissection and Mounting of Cepha loske letons of Third-lnstar Fly Larvae 



Cepha loskeletons of two species of fly larvae were examined for 

 morphological clues indicative of the modes of life of the larvae. 

 Third-instar larvae were killed in boiling water and dried on paper 

 towelling. Each was cut behind the cepha loske 1 eton so that only a 

 narrow band of integument still joined the two parts. Mext , larvae 

 were placed in 10% KOH and boiled gently until the unscl erot ized 

 tissues surrounding the cephaloskeletons had dissolved. At the com- 

 pletion of the KOH treatment, larvae were dried for 1-hr periods, 

 first in 70% and then in 90% ethanol . Larvae were stored in 100% 

 ethanol . While submerged in 100% ethanol, as much larval integument 

 and remaining soft tissues as possible were teased from the cephalo- 

 skeletons. The cephaloskeletons were stored overnight in phenol and 

 the remaining portions of the larvae were discarded. 



Cephaloskeletons were worked into a mixture of phenol -ba I sam and 

 placed in desired positions en mounting slides. Care was taken that 

 the specimens were completely covered with the phenol-balsam mixture. 



