The period of pupation is only of a few days' duration: the 
minimum being two, the maximum six clays. On bright sunny days 
they begin to hatch as early as 9 a.m. and continue to emerge 
during the heat of the day. A feu examples also hatched in tin- 
laboratory during the night, but this was apparently an exception to 
the rule. 
In order to rear the imagines the cocoons should be removed from 
the stream immediately they are formed ; and the leaves and stones 
to which they are attached should be placed in glass jars Covered nth 
ne muslm or chiffon. All that is necessary is to keep the material 
perfectly moist ; however, many imagines were successfully reared 
rom pupae which had become perfectly dry. (»„ .. 
the pupae he left in standing water. 
JZSnirr ,° f the imag ° the sk,n of »- P«P» spins aloqg 
forw a “ d e 3Teil ne at ° t f he the th ° raX and t " C ra P idly P-hes itself 
greyish or silvery Sa “’ e 8,,rro,,nded h >’ »« which Rives .t a 
The moment the in^T ^rlS'^f ° f "" ^ 
carried to the surface wii Pn n • " ' 
in contact in its rapid courf"? * ***** °^ eCt W,t ** w ^ch it a 
foothold instantly takes to win'o :< "o' and ll;,vin K gained a 
completely immersed in the T ccas,ol ™Hy the insects were seen 
either when waling a W\?^ « at perfect ease 
legs and antennae. I n such c- ^ ^ ^ P,antS or clea ™ng their 
the abdomen so that they tapered t & WingS Were fol, l"l partly round 
"if 1 " 6 SGen t0 a large air c ♦ * ^ behind ’ and this way 
observed in still Hus remarkable trait was 
m still water only. 
description of // te ^ 
Legs in two, coaiescent, pairs-' thi^ '; yl '. ndrira '. swollen posteriorly, 
first thoracic segment and pro.ee r , * 5 °? *** are *tt»*ed to the 
provided with little hooklets • th l "T beneath " le head and are 
the a 1 . and fo « S ' a ^ -ond pair (% M) are p|acfd at 
H " ° ,0 ° klets ^ranged in rP , SUcker whid > * surrounded 
- f Head (fig- 9. «) relatively T r trans verse senes. 
-T^^T^frepresented by two ' lab ‘ U ' n hroadl >' rounded 
' I° T - pot ! Antennae ^ ft <0 
