BULLETIX 1035, U. S. DEPAETMENT OF AGRTCULTUEE. 

 Table 2. — Length of the larval stadium. 



No. 



Date of 



Date 



Dura- 



Mean 



No. 



Date of 



Date 



Dura- 



Mean 



hatching. 



molted. 



tion. 



ature. 



hatching. 



molted. 



tion. 



ature. 









Days. 



°F. 









Days. 



°F. 



1 



Oct. 18 



Oct. 20 



2 



76 



7 



Feb. 1 



■Feb. 4 



3 



65 



2 



Oct. 28 



Oct. 31 



3 



77 



8 



Feb. 22 



Feb. 24 



2 



70 



3 



Nov. 15 



Nov. 19 



4 



75 



9 



Mar. 20 



Mar. 23 



3 



72 



4 



Dec. 10 



Dec. 13 



3 



70 



10 



Apr. 



Apr. 7 



2 



75 







Dec. 25 



Dec. 28 



3 



68 



11 



June 5 j June 7 



2 



76 



6 



Jan. 11 



Jan. 15 



4 



63 



12 



July 13 July 15 



2 



79 



THE FIRST XYMPHAL STAGE (THE PROTONYMPH). 



The first nymphal stage (fig. 3, d) differs from the larva in having 

 four pairs of legs instead of three and is slightly increased in size. 

 The extra pair of legs appears behind the last pair of legs of the 

 larva. The segments of the legs become longer, as do likewise the 

 bristles on the body and legs. The color of the body darkens. The 

 abdomen in this stage becomes elongated as compared to the larva. 

 The average length of the protonymph is 0.25 mm. 



For the most part the habits of the nymphal stage are similar to 

 those of the larva. As with the larval stage the protonymph stage is 

 divided into an active feeding period and a quiescent period prepara- 

 tory to molting. The average length for the first nymphal stage is 

 2.8 days. 



Table 3. — Length of the first nymphal ■■itadiiini. 



No. 



Date 

 emerged. 



Date 

 molted. 



Dura- 

 tion. 



Mean 

 temper- 

 ature. 



^,„ ; Date 



N°- :emer,'ed. 



Date 

 molted. 



Dura- ,^®^" 



1 

 2 

 3 

 4 

 5 

 6 



Oct. 20 

 Oct. 31 

 Nov. 19 

 Dec. 13 

 Dec. 28 

 Jan. 15 



Oct. 22 

 Nov. 3 

 Nov. 23 

 Dec. IS 

 Jan. 1 

 Jan. 18 



Days. 

 2 

 3 

 4 

 5 

 4 

 3 



"F. 

 76 

 77 

 75 

 70 

 68 

 63 



7 

 8 

 9 



10 

 11 

 12 



Feb. 4 

 Feb. 24 

 Mar. 23 

 Apr. 7 

 June 6 

 July 14 



Feb. 6 

 Feb. 26 

 Mar. 25 

 Apr. 9 

 June S 

 July 16 



Days. 

 2 

 2 

 2 

 2 

 2 

 2 



'F. 

 65 1 

 70 : 



7o 



76 1 



79 1 



THE SECOND NYMPHAL STAGE (THE DEUTO NYMPH). 



The second nj^mphal stage (fig. 3, 6^) is similar to the first nymphal 

 .stage except that it is much larger and more elongate. In its full- 

 grown condition, however, it resembles more the adult, though the 

 color is not as deep a red. It averages 0.38 mm. in length. 



The habits of the second nymphal stage are likewise similar to those 

 of the larva stage. The average length for the second nymphal stage 

 is 2.84 days. 



