THE DOCK FALSE-WORM. 



29 



Table XIX. — Summary of larval life of fourth generation of the dock false-worm, from 

 hatching to forming of pupal cell, Wenatchee, Wash., 1915. 



First instar. 



Second instar. 



Third instar. 



Fourth instar. 



Fifth instar. 



Sixth ins 



tar. 



_ . 



*- 





_ 



__ 





<« . 



«H 





<— 



^ 





<« 



<~ 





<-* 



^ 





Oi2 



03 



°^- 



s>> 



03 



u .c 



>> 



03 



u .d 



>> 



o w 

 03 



"^ 



;>> 



o3 



°.d 



>> 



° > £2 



°* 





i- 3 



fa § 



cj 



fa 3 







fa 3 





03 



t. 3 







fa 3 







u 3 







*3 



#• 



■O 



.ss 



J8; 



■o 



g"0 



*• 



-3 



S-3 



D« 



■a 



S3 



^S 



13 



*s 



SS 



■o 



F.2 



SR 



03 



B£ 



s& 



"3 



a.s 



a>. 



"3 



g.5 



a& 



03 



Si; 



a £ 



■3 



a.& 



fl£ 



"3 



a-o 



Sd 





3-d 



3 03 





fl-O 



3 03 





3-d 



3^ 





3-3 



3 03 





3-0 



3 03 





£.3 



£■0 



EH 



&.y 



^■u 



Eh 



». a 



J2- . u 



Eh 



z.a 



J2- -0 



EH 



z.a 



£' U 



Eh 



&.s 



£^ 



Eh 



l 



1 



1 



21 



2 



42 



i 



1 



1 



3 



2 



6 



2 



6 



12 



9 



1 



9 



7 



2 



14 



3 



3 



9 



9 



2 



18 



1 



2.5 



2.5 



2 



7 



14 



2 



2 



4 



13 



3 



39 



2 



3.5 



7 



8 



3 



24 



6 



3 



18 



4 



9 



36 



2 



4 



8 



4 

 4 



4 

 5 



16 

 20 



4 



1 



4 

 4.5 



16 

 4.5 



5 

 1 



4 

 6 



20 



4 

 4 



4 

 5 



16 

 20 



1 

 2 



10.5 

 11 



10.5 

 22 









13 





21 



4 



6 



24 



1 



10 



10 



1 



7 



7 



1 



6 



6 



1 



12 



12 



Av 



1.6 



3 



8 



24 















1 

 1 



8 

 10 



8 

 10 



1 

 1 



1 



13 

 14 

 17 



13 

 14 

 17 



Max 



Min 



4 

 1 



32 



At. 

 Max 

 Min 



I 88.5 



2.7 



10 



2 



25 



Av. 

 Max 

 Min 





76 

 .. 3 







138 



3,8 

 S 





At 



Max 





21 

 Av. 





86.5 

 . 4.1 









1 



15 





150.5 



Min 



1 













Max 

 Min 





10 

 2 



Av. 

 Max 

 Min 





.. 10 



17 



.. 6 







The foregoing table includes individuals from both fertile and par- 

 thenogenetic eggs, since there was but little difference between them. 



Life cycle of fourth generation. — Table XX gives a partial life cycle 

 of 13 individuals of the fourth generation, including the period from 

 oviposition to the forming of the pupal cell by the full-grown larvae. 

 This averages, 32.6 days for parthenogenetic individuals and 32.7 

 days for normal individuals. In order to arrive at the complete 

 length of the life cycle of individuals of this generation, we must add 

 to this approximately 200 days, which is the average time spent by the 

 larvae in the pupal cell, and also 10.5 days, which is the average 

 length of the spring brood (fourth generation) pupal period as shown 

 in Table II. This makes an average total of about 243 days, the com- 

 plete life cycle of the fourth generation. 



Table XX. — Length of partial life q/cle of the fourth generation of the dock false-worm, 



Wenatchee, Wash., 1915. 



I'artheno^enetic individuals. 



1 indi- 

 vidual 



Date of 



Egg dep- 



o iftion. 



Auk. 20 



..do.... 

 Sept. i 



do. . - 

 Sept. 2 

 Sept. 3 



Batching 



Ant'. 2\ 

 ..do. . .. 

 Sept. 7 

 . .do. . .- 

 Sept. !> 

 Sept. ii 



V 01 min)' 



pupal 

 cell. 



Sept. 16 



-.-pi 16 



Oct. 3 



Oct. 6 



Oct. in 



Oct. ii 



Total 



-■• aumbei ol 



Days ill- 



Egg 

 tage. 



i 

 i 



ii 

 6 

 7 

 8 



35 

 6.8 



Larval 



22 



23 

 26 



•J! I 



:;i 



.in 



161 

 28. 8 



Maximum life i minimum, 26 days. 



A ver- 

 age par- 

 tial life 

 cycle in 



days. 



26 

 27 

 32 

 35 

 38 

 38 



198 

 32 6 



