I'OMONA C'OLLEtiK JolKNAI. OK KNTtiWOI/U«iY 793 



— Small, nearly as louj,' as wide, with distiuet, but short, anli-iiiiul tubvrcles, 

 pointed iu l'rout,ilark with anilicr or hrowu I'l-out. Kyts — Dark red, to lintwn. 

 Anil «/wit — (Figure '2bl, 1 ). Louyer tluiu half the length of the body, reaching 

 to the bases of the eoruieles, with very few hairs, iuibrieated; articles 1 uud 

 11 dark amber brown, III dark amber base and remainder amber, IV, \', VI 

 dark brown to nearly blaek. Lengths of the articles: 1, U.U'J mm.; 11, K.Uti 

 mm.; Ill, 0.3 mm.; IV, 0.2 nun.; V, 0.17 mm.; VI, O.iiG mm., (spur or lilament, 

 0.47 mm.j ; toUd 1.38 mm. From these measurements it will be seen that the 

 articles bear a similar relation to each other as do the articles of the antenna- 

 of the winged female ami that the lilament is longer than article III. (There 

 seem to be no inilividuals in which this is revei-seilj. Sensoria only on articles 

 V and VI and on these normal. Kuslruin — lieaching t<j back margin of the 

 second coxie, amber with ilark base and tip. I'ruthurax — Slightly wider than 

 the heail, with ilistinct lateral tubercles. All thora.x. black and distinctly 

 segmented with mcsothorax very short. Abilomi n — Smooth, dull black or 

 very dark green, with one lateral anterior and a lateral jKjstcrior tubercle on 

 each side, segmentation ou the dorsum partial or indistinct. Anal plate black 

 or very dark. (Vruidcs— (Figure 251, Ij;. Cylindrical, smooth — not imbri- 

 cated as in the winged forms — not reaching to the tip of the abdomen, .s»jme- 

 times slightly tlaring in the middle, constricted just before the mouth which is 

 llared, black, length 0.31 mm., average width O.Ool mm. Lrys — Lighter than 

 in winged form; coxa; amber-yellow; femora with tip and front darker; tibiiu 

 same as femora; tarsi dark brown. Utt/U — Slender, nearly cylindrical, half 

 as long as the cornicles, dark green to nearly black, hairy. 



Hants — Occurs iu more or less limited numbers on the ears and ta.s.«iels of 

 the common sweet corn. In the coru-growing States of the Mississippi Valley 

 this insect is a most serious pest and much study has been given to perfect 

 control methoils. It attacks practically all members of the sorghum or corn 

 family, and has been reported from practically every State in the United 

 States and from the Hawaiian Islantls. I'rof. Clarke reported it from this 

 State in the year 1903, but since that time it has received little or no attention. 



Locality — Collected by the author in the vicinity of Santa I'aula. He- 

 ported from the central part of the State by I'rof. Clarke and W. .M. Oavid.son. 



Date of collection — Occurs throughout the summer month.s. Specimens 

 studied were collected July 28, 1911. Serial number 48. 



\aliiral Enemies — This species is quite extensively parasitized by internal 

 parasites. The larvie of the native Scymnus (S. sordidus Horn) and the 

 larvie of Syrphid Flies play an important part in keeping it down. 



Rhopalosiphum nymphaeae Linn. 

 (Pond Lily Ai)hid) 



17G7 Aphis nymplMcac L\un. Syst. Nat. II, p. 734. 



1794 Aphis nyinphiicae L'nm. P'abr. Ent. Syst. IV, p. 214. 



1801 ^/)/ii.s /ii/»i/>/i(i(rtf Linn. Schrank. Fn. Hoica. II, p. 117. 



1801 Aphis biitomi Schrank. Fn. Boica., p. 114. 



