50 



BULLETIjST 351, V. S. DEPARTMENT OF AGEICULTUEE. 



Alto, Pa., during the winter of 1912-13 passed this period with a 

 mortality of less than 10 per cent. At Midvale, Pa., during the winter 

 of 1913-14, specimens upon poorly nourished trees had a mortality 

 as high as 54 per cent. Neither birds nor other animals make a 

 noticeable attack during hibernation, but there is a strong parasitic 

 attack upon the young females before hibernation. This was espe- 

 cially noticeable during the first week m September. 



development of the male. 



Male Larva, Second Instar. 



In this instar the elongation of the larva and the secretion of the 

 puparium undoubtedly start immediately after the first molt, but 

 it is usually five or six days before they can be detected. The male 

 mcreases, as is shown in Table XXX, from an average length of 1.03 

 mm. to an average length of about 1.706 mm., and m width from an 

 average of 0.421 mm. to an average of about 0.830 mm. There is 

 also an appreciable increase in height. 



Table XXX.- — Average measurements of the male terrapin scale in the second instar at 

 various ages between the twenty-fifth and thirty-fourth days, at Mont Alto, Pa. 



Year. 



Date 

 emerged. 



Age. 



Number 

 of speci- 

 mens. 



Average 

 length. 



Average 

 width. 







Days. 





Mm. 



Mm. 



1912 



Aug. 9 



25 



1 



L031 



0.468 



19i2 



...do 



26 



2 



1.218 



.421 



19l3 



Jime 24 



30 



14 



L628 



.830 



1912 



Aag. 9 



31 



A 



L579 



.642 



1913 



June 26 



32 



13 



L661 



.809 



1913 



Jime 24 



33 



13 



L621 



.813 



1913 



...do 



34 



8 



1.706 



.777 



In 1912 the instar extended to the fortieth day, but practically 

 all males had shrunlv in preparation for the second molt by the 

 thirty-fifth day. 



The followmg table compares the measurements of 54 females in 

 the second instar with 48 males of the same rearmg, and shows that 

 the females average 0.168 mm. wider and 0.111 mm. shorter than the 

 males. 



Table XXXI. — Comparative measurements of male and female larvse of the terrapin scale 

 during the second instar, Mont Alto, Pa. 



Age. 



Date 

 emerged. 



Number 

 males. 



Length 



of 

 males. 



Width 



of 

 males. 



Number 



of 

 females. 



Length 



of 

 females. 



Width 



of 

 females. 



Days. 

 30 

 32 

 33 

 34 



June 24 

 June 26 

 Jiuie 24 

 ...do 



Total.... 

 Average. 



14 

 13 

 13 



8 



Mm. 

 1.628 

 1.661 

 1.621 

 1.706 



Mm. 



0.830 

 .809 

 .813 



.777 



7 



16 

 20 

 11 



Mm. 

 1. 507 

 1.506 

 1. 587 

 1. 575 



Mm.. 



0.982 

 .937 

 .978 



1.012 



48 







54 







1.854 



.807 



1.543 



.975 









