THE SHABP- HEADED GRAIN LEAFHOPPER. 



9 



Table IV. — Length of nymphal stage of the sharp-headed grain leaf hopper , Tempe, 



Ariz., 1914 — Continued. 



SECOND GENERATION, MAY AND JUNE, 1914. 



o 



b£ 



® bi 

 g ® 



as 

 a* 



>5 



z; 



"c 

 E 



H 



c8 



O 



e 



c3 



ft 



<a 



■SB 



bjo 



a 

 i-l 



■d 



a 



o 

 o 



W ^-5 



°a 



CD 



ft 



a 



o 

 a 



CD . 



^C3 

 O-g 



5-S 

 tuo'™ 

 PI 



73 



3 

 °1 



o 



+^> 

 03 

 ft 



■3 



tsn'" 



a 



»3 



u 



o 



CD 



"§ 

 ft 



a 



o 

 ^ u, 



"3| 



a fl 

 -fj.j-i 

 bo 



CD 

 ft 



a 



CD 

 03 



ft 



cc 

 O c3 



■a a 



bo 



g 



ft 



°CD 



bo 



a « 



bo m 



§d 



— a 



May 15 

 May 14 

 May IS 

 Mav 16 

 May 15 

 May 14 

 Mav 15 



May 21 

 May 22 

 May 25 

 Mav 22 

 May 21 

 May 18 

 May 21 



Days. 

 6 

 8 

 7 

 5 

 6 

 4 

 6 



May 26 

 May 28 

 ...do 

 May 23 

 May 26 

 May 25 

 May 26 



Days. 

 5 

 6 

 3 

 2 

 5 

 7 

 5 



May 31 

 Jiuie 2 



May 29 

 May 28 

 May 29 

 June 1 

 May 28 



Days. 

 5 

 5 

 1 

 5 

 3 

 7 

 2 



June 7 

 June 6 

 June 4 

 June 1 

 June 2 



Days. 

 6 

 4 

 6 

 4 

 4 





Days. 



Days. 















June 7 

 June 8 



6 

 6 



22 

 22 

























6 



4.7 



4 



4.8 



6 



22 















THIRD GENERATION, JUNE AND JULY, 1914. 



June 28 

 Do.... 

 Do.... 

 Do.... 

 Do.... 



Av 



Julv 1 

 July 2 

 July 1 

 June 30 

 July 1 



3 

 4 

 3 

 2 

 3 



July 6 

 July 5 

 July 6 

 July 7 

 July 4 



5 



3 

 5 

 7 

 3 



Julv 11 

 July 13 

 July 12 

 ...do 



July 8 



5 

 8 

 6 

 5 



4 



July 14 

 July IS 

 July 17 

 July 15 

 July 13 



3 

 5 

 5 

 3 

 5 



July 21 

 July 23 

 July 22 

 July 26 

 July 19 



7 

 5 

 5 

 5 

 6 



23 

 25 

 24 

 22 



21 



3 



4.6 



5.6 



4.2 



5.6 



23 















FOURTH GENERATION, AUGUST, 1914. 



Aug. 1 

 Do.... 

 Do.... 

 Do.... 



Aug. 4 

 Aug. 5 

 Aug. 3 



...do 



3 

 4 

 2 

 2 

 3 

 4 



Aug. 9 

 Aug. 10 

 Aug. 8 

 Aug. 7 

 Aug. 9 

 Aug. 8 



5 

 5 

 5 

 4 

 5 

 3 



Aug. 12 



...do 



Aug. 13 

 Aug. 11 

 Aug. 13 

 Aug. 12 



3 



2 

 5 



4 

 4 

 4 



Aug. 16 

 Aug. 17 

 Aug. 18 

 Aug. 16 

 Aug. 19 

 Aug. 18 



4 

 5 

 5 

 5 

 6 

 6 



Aug. 20 

 Aug. 21 



...do 



Aug. 22 



...do 



...do 



4 

 4 

 3 

 6 

 3 

 4 



19 

 20 

 20 

 21 

 21 

 21 



Do.... 

 Do.... 



Av 



Ana. 4 

 Aug. 5 



erage > 



3 



4.5 



3.6 



5.1 



4 



20.3 













FIFTH GENERATION, SEPTEMBER, 1914. 



Sept. 2* 







Sept. 9 5 1 





Sept. 18 « 



Sept. 28' 





26 











SIXTH GENERATION, OCTOBER AND NOVEMBER, 1914. 



Oct. 8 » Oct. 11 » 





Oct. 17 » 





Oct. 23 » 





Oct. 30 





Nov. 9 





34 



1 Total of averages of rasters, 25.5 days. 



2 Total of averages ofinstars, 23 days. 

 i Total of averages ofinstai '' 



1 About 20 nymphs. 



<• Nyrn;. ■! and third Instars. 



6 Nymphs in fourth instar. 

 ' Sixteen adults. 

 8 About 15 nymphs. 

 o About this date. 



From Table IV it will he seen thill it took the nymphs of tho fourth 

 generation the shortest time for development and growth, being an 

 average of 20 days from egg to hist molt. While tho lengths may 

 viiiv from Beason to season and from year to year, it is evident that 

 during the summer months nymphs develop in about half tho time 

 of those of the hr-t spring generation'. 



