December, '14] TOWER: life history of PROSPALTELLA 425 



Respiration during the early life of this form is carried on in the 

 same way as that of the first larval stage, but later as the fluid con- 

 tents of the scale is consumed and an air space forms in the scale, some 

 of the spiracles which have developed no doubt open and function. 

 Without doubt by the time all the fluid content of the scale is con- 

 sumed all the spiracles are fully developed and function. 



The stomach is, as in the previous stage, a blind sac well filled 

 with food. Its contents is even more thoroughly churned by more 

 powerful contractions of the stomach walls. These contractions may 

 start at either end running the length of the stomach, or starting at 

 both ends run to the middle, or again starting in the middle run to 

 both ends. The contents are at first the same yellow color as the 

 scale, due to the fat globules swallowed, but later they become at first, 

 due to digestion, a light orange, changing to dark orange and previous 

 to being excreted a deep red to black color. 



Feeding is carried on in the same manner as has been described for 

 the first stage larva except that in the last part of this stage the man- 

 dibles, which are blunter and less curved than in the first stage, are 

 used in destroying the internal organs and in scraping clean the inside 

 of the skin of the scale. 



The proctodseum is partially developed in the early part of this 

 stage, but does not become fully developed or open until after the 

 larva has consumed the entire contents of the scale and has entered a 

 short quiescent period during which the contents of the stomach com- 

 pletes its digestive processes and is prepared to be excreted. 



Following this period the waste, which has been accumulating in 

 the stomach during the life of the two larval forms, is passed and is 

 usually deposited along the lateral margins of the skin of the scale or 

 at the ends. The chitmous portions of the proctodseum are passed 

 out with the last of the waste and no doubt the chitinous portions of 

 the fore-gut and trachese are also gotten rid of at this time. 



The larva, following the passing of its waste, is usually found lying 

 on its back with its head at the head end of the swollen skin which 

 has dried and become a hardened case in which the parasite now 

 pupates. 



Pupation and the Pupa 



Rapidly following the passing of the waste the larva usually begins 

 to show differentiation into the three principal regions: namely, the 

 head, thorax and abdomen. Following this condition, which exter- 

 nally marks the beginning of the pupal stage, pigmentation begins in 

 the antennae and its segments commence to form. 



This coloration is quickly followed by that of the eyes, the dusky 

 band of the fore-wings and a small portion of the ventral abdominal 



