December, '14] TOWER: LIFE HISTORY ^F PROSPALTELLA 429 



and backward through the scale covering and into the scale until 

 the tip of her abdomen almost touched the scale covering. While it 

 was not possible to see the egg deposited in the scale it is evident that 

 this takes place for, in the examination of first-stage scales, one finds 

 the egg lying mthin the body. 



The examination of mature first-stage scales, w^hich are wintering 

 over, shows eggs in all stages of development and even live larvae 

 may be found in the early stages of the second-stage scales as they are 

 forming within the skin of the first-stage scales. From the large num- 

 ber of observations made upon first-stage wintering scales, which were 

 brought into the laboratory to complete their development, it seems 

 that the majority of the eggs hatch just as the second-stage scale is 

 forming within the first-stage scale, although many hatch after the 

 molt previous to the feeding period of the second-stage scale. Un- 

 developed and partially developed eggs have also been found in second 

 stage scales after feeding and growth have begun. These scales de- 

 veloped from first stage scales in the laboratory and hence it is seen 

 that these eggs were laid late in the life of the first-stage scale. The 

 above data indicate that oviposition takes place all through the life 

 of the first-stage scale, after it has settled down, and that normally 

 the majority of the eggs are laid early in the life of the young scale and 

 these complete their development in mature second-stage scales, while 

 those eggs which are deposited late in the life of the first-stage scale 

 hatch so late in the life of the second-stage scale that it would not be 

 damaged enough by the parasite to prevent it from passing into the 

 third stage. This, it is seen, would account for the fact that some of 

 the parasites emerge from early third-stage scales. However, there 

 is a possibility of the parasite ovipositing in second-stage scales, but 

 this seems unlikely as even its early life is additionally protected by 

 the first exuviium and in its later life it seems even less likely due to 

 its large size as compared with first-stage scales normally oviposited in. 



Large numbers of the scales are oviposited in twice and possibly 

 even more times, but twice is the most that has been observed. As a 

 rule w^hen two eggs are found in one scale they are widely separated 

 in development, showing that they w^ere laid at different times and 

 hence by different individuals. In other cases one often finds an un- 

 developed or a partially developed egg and a live feeding larva in the 

 same scale. Only two cases of like development have been observed; 

 one was in which the two eggs found were at the same stage of devel- 

 opment, and the other was in which the two larvae were of approximately 

 the same age. However, from the large number of observations made, 

 it should not necessarily be taken that the same adult laid the two 

 eggs in the scale, but rather that the scale in these cases was oviposited 



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