HEMIPTERA—HOMOPTERA— APHIDES. 247 



1. Archilachnus pennatds. 



PI. 18, Figs. 1, 15-17. 



Archilachnita peiinatiia Buckt., Monogr. Brit. Aphides, IV, 177, PI. 133, Fig. 3 (1883). 



As preserved, the head and thorax are uniform and considerably darker 

 than the abdomen. The body is stout. Fore wing more than two and a 

 half times longer than broad, with the postcostal vein thick, straight, and 

 uniform, running into the very long and fusiform stigma, and separated by 

 a narrow space from the margin, which is gently convex, and so a little more 

 distant at base. First oblique vein arising at one-third the distance from 

 the base of the wing to the stigmatic vein, straight, parting from the post- 

 costal at an angle of about sixty degrees ; second oblique vein arising very 

 close to the first, straight, or very slightly sinuate or arcuate, parting from 

 the postcostal at an angle of forty-five degrees ; first discoidal cell much 

 widened distally, being five or six times broader on the hind margin than 

 at base. Cubital vein arising twice as far from the second as the second 

 from the first oblique vein, with its first branch completely parallel to 

 the second oblique vein, first forking at a trifle more than one-third the 

 way out, and again about half-way from the first fork to the apex of the 

 wing, varying in individuals, at the first fork bent slightly but beyond 

 almost perfectly straight. The stigmatic vein is arcuate and parts sometimes 

 widely, sometimes narrowly from the stigma, so that the stigmatic cell is of 

 variable slenderness, though always more than a third as long as the wing. 



Length of body, 4°"» ; of fore wing, 6.6°"° ; hind femora, 2.5°'°' ; hind 

 tibiae, 3.75°"°. 



Florissant. Five specimens, Nos. 177, 4615, 6993, 9221, 12727. 



2. Archilachnus mudgei. 



The single specimen is excellently preserved on a dorsal view, except 

 that the overlapping fore wings are somewhat confused, lying upon the top 

 of the back, and that one wing is doubled upon itself The body is rather 

 slender, the head and thorax darker than the scarcely perceptible abdomen 

 and apparently mottled. Fore wings with the postcostal vein and stigma 

 as in A. pennatus, the first oblique vein arising at a little more than one- 

 third the distance from the base of the wing to the stigmatic vein, but other- 

 wise like the second oblique vein, as in A. pennatus ; the first discoidal cell 



