134 



MISCELLANEOUS PAPERS. 



The number of molts in the oviparous generation is four, as in 

 the viviparous generation. From Table VI, showing the periods 

 between the molts, it appears that the males are more deliberate in 

 their growth and require a longer time than the females for their 

 full development. 



Table VI. — Periods of molts of Aphis maidi-radicis, oviparous generation, 1906. 



DESCRIPTIONS." 



Aphis maidi-radicis Forbes. 



VIVIPAROUS GENERATION. 



Before first molt and less than 1 hoar old. — General color pale pea- 

 green. Legs and antenna^ colorless and transparent. Eyes red. 

 Measurements : Length of body, 0.882 mm. ; width, 0.400 mm. ; 

 antenna, 0.327 mm. 



After first molt and not more than 21^ hours old. — General color 

 pea-green. Antennje almost transparent, excepting last segment, 

 which is darker. Only 5 noticeable segments in the antennje. Eyes 

 red. Tip of beak darkened. Legs almost transparent, excepting 

 tarsi, which are almost black. Cornicles small, slightly darkened at 

 tip. Measurements: Length of body, 0.927 mm.; width, 0.509 mm.; 

 antenna, 0.339 mm. 



After second molt and 72 to 96 hours old. — General color pea-green. 

 Ultimate segment of antennae dark. Eyes reddish brown. Legs 

 darker than body color. Tip of abdomen dark. Cornicles dark, 

 being darkest at apex, short and very slightly incrassate in mid- 

 dle. Measurements : Length of body, 1.418 mm. ; width, 0.709 mm. ; 



« In giving the number of segments of the antennae I have not, as most writers 

 do, counted the filament as a separate and distinct segment. There is certainly 

 no articulation between the thickened basal portion and the filament of this last 

 segment; and, thus, they can not be referred to as distinct segments. 



The measurements, and the observations on colors, were taken from live 

 specimens unless otherwise stated. Color terms are according to Ridgway's 

 " Nomenclature of Colors." 



