50 BULLETIN 826, U. S. DEPARTMENT OF AGRICULTURE. 



as type, and he used Siphocoryne in a different sense with xylostei 

 Schrank as type. Such a procedure is inadmissible, and Kirkaldy 

 therefore renamed this genus Hy ad aphis. 



The genus Coloradoa Wilson was erected with rufomaculata Wilson 

 as type. Although much smaller, this species is essentially like 

 nympheae in structure, and we therefore consider the genus a syno- 

 nym of Rhopalosiphum. 



The genus Siphonaphis Van der Goot was erected with nympheae 

 L. as type. Having the same type-, therefore, it must become a 

 synonym of Rhopalosiphum. Lahorensis Das is quite similar. 



Characters. — Head without prominent antennal tubercles. Antennse of six seg- 

 ments with the usual subcircular sensoria present. Wing venation normal. Cor- 

 nicles moderately long and slender, slightly swollen near their distal extremities. 

 Cauda rather elongate, not as long as the cornicles, and not broad. Abdomen without 

 a caudal horn or projection above the cauda. Males usually winged; oviparous 

 females usually apterous. 



Type (fixed by Gerstaecker, 1856), Aphis nympheae L. 



Genus SANBORNIA, n. gen. 

 Plate VII, F-L. 



The genus Sanbornia is erected for a peculiar form living on 

 juniper at College Station, Tex., and forwarded to the Bureau by 

 Charles Sanborn. This species was determined as undescribed by Mr. 

 Pergande who had planned to publish on it. He had given it the 

 name juniperi. The type is in the U. S. National Museum (Cat. 

 No. 23064). 



Characters. — Head without prominent antennal tubercles. Antennae of five seg- 

 ments, armed with circular sensoria. Fore wings with the media once branched, 

 hind wings with only the media present, cornicles minute; cauda elongate. Apterous 

 form with four-segmented antennas and with a prominent mushroom-like projection 

 on the vertex. 



Type, Sanbornia juniperi Perg. 



Sanbornia juniperi Pergande, n. sp. 

 (Description by Mr. T. Pergande.) 



Apterous form. — The head is most remarkable in front, having a large, squarish, 

 bilobed projection about the middle and each side of it; close to the insertion of the 

 antennae is a prominent, short, and conical protuberance. There is also at the inner 

 side of the first antennal joint a long and slightly conical protuberance. The antennae 

 are but four-jointed, the spur shorter than the basal section of the joint. Nectaries 

 are not visible (?); the tail is rather long and uniformly elongate conical; the tarsi 

 are very short, the first joint appears to be minute, and in alcoholic specimens seems 

 to be withdrawn into the tibiae; the last abdominal segment is semicircular. 



