ON THE LIFE HISTORY OF UGIMYA. 29 



tlie end of about thirty liourö it becomes black. In this stage, 

 the contents of the puparium are mostly dissolved into a milky 

 white fluid containing large quantity of tat, without apparent structure 

 of any sort. 



At the end of the third day, this white fluid solidifies and 

 becomes an oblong mass or pupa, enveloped with two thin mem- 

 branes — the outer and the inner. Tlie outer membrane, which is 

 slightly thicker than the other and tinged light yellow, lies close inside 

 the hardened larval skin or puparium, while the inner (pupa- skin ) 

 which is colorless and transparent covers directly the oblong mass 

 which later becomes the pupa. The space between these two mem- 

 branes is filled with a small amount of a colorless liquid which is 

 necessary to protect the contained pupa from dessication. Generally, 

 the anterior smaller end of the pupa can easily be distinguished from 

 the broader posterior end (P/. V,ßg. 8). Dorsally the anterior end 

 ( Fl. V, fig. 9 a) is separated by a slight constriction from the rest of 

 the body, and near the front edge of the same end lies a pair of tuber- 

 cles ( PL V, fig. 9h) from each of which is projected a sort of a short 

 black horny spine ( respiratory tube ). Ventrally on the same end are 

 developed three pairs of small incomplete legs ( PI. V, fig. Sa), those 

 of one side meeting with their fellows of the opposite side along 

 the median ventral line. At the base of the legs are produced two 

 lamellar sac-like paired bodies, the wings, {PI. V, fig. 8h), each of 

 which covers the greater portion of the last two legs on its own side. 



At the end of a week, the body of a pupa is plainly divided by a 

 deep constriction ( PI. F, fig. 10 c) into two regions — the anterior be- 

 ing much smaller than the posterior. From the former, the head and 

 thorax of the adult are developed ; and from the latter, the abdomen. 

 At this stage, the paired tubercles ( 7^/. F, fig. 10 a ) which lay in the 

 previous stage close Avith each other at the front end of the body 



