HEMIPTEEA—HOMOPTERA— APHIDES. 253 



3. Sbenaphis lassa. 



This small species is represented by a single individual, with nearly all 

 the legs preserved in an unusual manner, but the wings not so completely. 

 The body is black throughout, the hind femora longer than the abdomen, 

 the hind tibiae as long as the body. The wings have the postcostal vein 

 and stigma precisely as in the last species. The first oblique vein is straight 

 or at the tip slightly arcuate, parting from the postcostal at an angle of about 

 fifty degrees, the second oblique vein distinctly arcuate on its apical half, 

 parting from the postcostal at an angle of forty -five degrees, and separated 

 from the first by a slightly wider interval than in the other species described ; 

 the first discoidal cell is about four times as bi'oad on the hind margin as at 

 the base. The cubital vein, arising nearly three times as far from the second 

 oblique vein as the latter is from the first, takes a course above the middle 

 of the area left to it, approaching very close to the stigmatic vein ; it forks 

 first about quarter-way to the hind margin and again about opposite the 

 stigmatic vein, which, with the stigmatic cell, is as in S. uhleri. 



Length of body, 3.25°"" ; fore wing, 5.5™" ; fore femora, 1.15""" ; fore 

 tibiae, 1.7"""; middle femora, 1.4™"; middle tibiae, 2.3™™ ; hind femora, 2™™; 

 hind tibiae, 3.25™™. 



Florissant. One specimen, No. 12994. 



5. APHANTAPHIS gen. nov. (acpavro?, Aphis). 



Head without frontal tubercles, the antennae being inserted in sub- 

 lateral pits ; they are longer than the fore wings, very slender indeed, the 

 third joint very long. Fore wings with the stigmatic vein arising from the 

 middle of an exceedingly slender and tapering stigma, the stigmatic cell 

 nearly half the length of the wing. Cubital vein twice forked, the first time 

 at a very slight distance from its origin, which is scarcely before the middle 

 of the space between the first oblique and stigmatic veins, the second time 

 half way thence to the tip of the wing. Second oblique vein arising slightly 

 nearer the cubital than the first oblique vein, the first so near the base of 

 the wing as to be very short, and the first discoidal cell between them only 

 about twice as wide at the hind margin as at base. Legs long and slender, 

 the hind tibiae and tarsi nearly equaling the length of the wings. 



A single species is known. 



