SOUTH AFRICAN BAGWORMS. 675 



July, and reached a maxiniuiii during- the second week in 

 August, the average duration of the pupa stage of the female 

 being two months and seven days. 



We thus see that, although the females keep on feeding for 

 a month longei' than the males, yet their pupation period is 

 roughly a month shorter, so that adult males and females 

 appear almost simultaneously. 



(8) The Imago. 



Emergence of Males. — When the time of emergence 

 approaches, the pupa works its way pai'tly out of the lower 

 end of the bag, until it protrudes far enough to free the wing- 

 cases and the legs. The pupa then splits in the usual manner, 

 and the moth after emergence crawls on to the side of the 

 bag, where it remains motionless to allow the wings to dry 

 and harden. The time from the first extrusion of the pupa 

 until the moth is ready to fly is very short, the entire process 

 being accomplished in about ten minutes. Emergence takes 

 place in the middle of the day, generally between the hours 

 of 11 a.m. and 3 p.m. The moths are active and on the wing 

 during the hours of the brightest sunshine. Sunshine is a 

 very important agent in promoting emergence, and in young 

 plantations, or on the edges of the blocks, where the sun has 

 more easy access to the bags, the moths appear earlier than 

 in the centre of old shady plantations. 



Emergence of Females.— The female does not leave the 

 chrysalis case. When mature, the anterior part of the pupa 

 is pushed off like a cap, exposing the head and the first two 

 thoracic segments of the female moth. The seam along 

 which this cap is severed is on the ventral side fairly regular ; 

 it follows one of the intersegmental incisions, and is here pro- 

 bably made by a restricted turning motion of the head of the 

 insect, which is armed with two pointed prongs on its ventral 

 aspect (text-fig. 5, c). The ventral slit thus made, a pushing 

 forward of the enclosed moth removes the anterior part of 

 the pupa case, which thus breaks along the edge of one of the 



