SPERMATOGENESIS OF PEDICULUS VESTIMENTI. 379 



1918. Eggs. Hatched. 



Sept. (Mated Aug. 22) 



8 .................................................... 6 5 



9 .................................................. 5 5 



! ...... ...... 5 5 



11 .................................. .................. 6 4 



12 ..................... ..................... 5 5 



13 .................................................... 5 6 



14 ... 54 

 1 5 Female dead ......................................... i 5 



"3 

 16 ......................... 5 



f 5 hatched from eggs deposited ....................... 9-7 1 



I I ..... 9-8 / 



/ 3 hatched from eggs deposited ........ . . 9-8 \ 



li " " ................. 9-9 / 4 



[ 2 hatched from eggs deposited ....................... 9-8 1 



19 13 ....................... 9-9 6 



I i ....9-ioJ 



1 hatched (the last) of eggs deposited ................. 9-9 X | 



3 from eggs deposited ....................... 9-10 i 





2 ..9-I2 



1 hatched (the last) of eggs deposited ................. 9-10 } 



2I 5 (the last) " ................. 9-11 



2 from eggs deposited ....................... 9-12 f 



3 ..9-I3J 



(2 hatched (the last) of eggs deposited ................. 9-13 ] 

 2 from eggs deposited ....................... 9-14 \ 5 



i ..9-iSJ 



2 3 3 hatched (the last) of eggs deposited ................... 9-14 3 



The last egg deposited 9-12 not hatched, nymph partly 

 emerged but dead. 



SUMMARY. 



If we omit the one egg deposited the day the female died the 

 daily average for the remaining 112 eggs is 4-9- 1 



113 eggs were deposited from August 23 to September 15 and 

 all of these developed to the nymph stage, though six failed to 

 completely emerge from the egg. 



The above record shows that the male died September 6 and 

 the female died September 15. From September 6 each daily 

 deposition of eggs was isolated to determine how long the eggs 

 were fertilized after the last mating (September 5). The record 

 shows that all the eggs developed and that all hatched but one. 



1 Bacot found the daily average to be 5.1 and Nuttall's experiments demon- 

 strated that under natural conditions, i.e., when the lice lived continuously on 

 the host, the daily average increased to 9.7. 



