112 Journal New York Entomological Society. [Voi. xvii. 



is lost, in the other the second branch. Fig. lo, e-f, represents two 

 stages in the reduction of the upper branch of the second fork. 



In other respects this species is not especially variable. While 

 studying it at Washington I noticed several other examples with the 

 third discoidal i -forked, reminding one of the normal venation in 

 Toxoptera. I noticed that the single forked third discoidal was a fre- 

 quent variation in Aphis {SipJiocoryne') avcine which I collected on 

 wheat at several points in Oklahoma and Georgia in the fall of 1907. 



The following descriptions are all from balsam mounts. No color 

 notes were made of the H. aqui/egicv-flavus coWtcted in the fall. The 

 colors of all other forms are from the living insects, high power hand 

 lens, daylight. The bodies of these aphids preserved in 70 per cent, 

 alcohol and mounted with the usual technique are not shrunken enough 

 to be unfit for measurements judging by comparison with formalin 

 material. Measurements at the best are only approximate, the size 

 depending greatly on the supply of food and other conditions. For 

 this reason I do not see the necessity for measuring many specimens. 

 I have adopted the practice of picking out two of the smaller speci- 

 mens, two typical and two of the largest from a large number col- 

 lected, and thus the average size can be obtained accurately enough 

 for systematic purposes. Whole mounts of H. aquilegia-flaviis usually 

 show a flat vertex ; whether the median ocellus is visible or not on the 

 vertex depends, of course, on the position of the object. 



Hyalopterus aquilegiae-flavus (Kittel). 



Aphis AquilegicEjlava sp. nov., Kittel, Mem. Soc. Linn. Paris, Vol. 5, 1827, p. 

 48. On leaves of Aquilegia vulgaris L. , France. Description of winged form. 

 (The short cornicles, long cauda, dark bands on the abdomen and the oval shape are 

 sufficient evidence that this is the same as Walker's species.) 



Hyalopteriis flavus Kittel, Schouteden, H., Cat. d. Aphid, de Belg., Vol. 12, 

 1906, p. 230. Rose and Aquilegia vulgaris in Belgium. Synonomy ; restores Kit- 

 tel' s name in part. 



Hyalopterus aquilegia n. sp , Koch, C. L. Pflanzenlause, 1857, pp. 19-20, pi. 

 4, figs. 25-26. Descriptions and colored figures of winged and wingless viviparse 

 Germany; stem-mothers (Altmiitter) isolated on under side of leaves of Aquilegia 

 vulgaris towards the end of May, winged viviparre appearing early in June. (Evi- 

 dently then, the hibernating eggs must have been laid on this host without a migration. ) 



Aphis trirhoda n. sp., Walker, Francis, Ann. Mag. Nat. Hist. (London), Vol. 

 4 (2d ser. ), 1849, pp. 45-46. Descriptions of winged and wingless viviparte. Mi- 

 gration from rose to columbine in May. Brief description of winged male. 



Hyalopterus trirhoda (Walker) Passerini, G., Aphididas Italicse (Archivio per la 

 Zool. I'Anat. e. la Fisiol., Modena, Vol. 2, fasc. 2), 1863, pp. 149, 150. Italy ; 

 Aquilegia vulgai-is in summer and Eosa indica and H. gallica in autumn. Difteren- 



