NATURAL SCIENCES OF PHILADELPHIA.. 75 



species is necessary to decide this point. A. pnrpuraseetu, Ubler, must be 

 excluded from this genus, as the presternum is not spined ; it may belon 

 Pterolepis, Rambur, but I have seen no species of this genus, and therefore 

 cannot speak positively. 



A. Stevensonii, n. sp. 



Female. Purple, mottled with yellow ; form and coloring somewhat similar 

 to A. purpuraseens, Uhler, but smaller and slenderer in all its parts. Face 

 white, the transverse suture below the front fuscus; tips of the mandibles 

 piceous ; palpi pale, the penultimate joints of the maxillary palpi striped with 

 purple above ; antenna? long and slender, reaching nearly to the extremity of 

 the ovipositor, dusky ; cranium cinereous, with the vertex, and a line extending 

 back from each eye, dull white. Pronotum short, not carinated, a slight 

 transverse incision near the front; the two oblique dorsal impressions very 

 narrow and dark; surface smooth, lurid ; a large black spot occupying the 

 central portions of the sides behind the transverse incision; lateral margins 

 broadly and anterior margins narrowly bordered with pale yellow; posterior 

 angles tipped with piceous-black. Tegmina hid beneath the pronotum. Ab- 

 domen dull purple, somewhat darker along the sides. Ovipositor slightly 

 curved beyond the middle, piceous at the tip ; cerci slender, hairy. Beneath, 

 dull white. Anterior and middle legs short, femora slender and straight; 

 posterior legs very long and slender, femora and tibiae each the length of the 

 body omitting the head ; all pale, purplish-yellow ; femora smooth ; tibia with 

 spines irregularly placed on the angles, also on the rounded portion, black 

 at the tips. The spine above the anterior coxa pale, slender, and bent 

 abruptly downward. 



Length 1-13 in. ; pronotum -26 in. ; posterior femur -93 in.; ovipositor -75. 



Hab. Southern Colorado, on elevated grassy terraces near the mountains ; 

 and the parks. Collected by C. Thomas while accompanying Dr. Hayden's 

 Geological Expedition to Colorado and New Mexico. 



It is named in honor of Mr. James Stevenson, a member of the expedition, 

 who has for years accompanied Dr. Hayden in his western explorations, and 

 has been a diligent collector of specimens in all departments of Natural 

 History. 



A. minutus, n. sp. 



Male. Similar in coloring and appearance to the A. Stevensonii. Face 

 mottled with purple; a dark spot below each eye; a narrow yellow line 

 running back from the upper corner of the eye ; cranium cinereous, head 

 somewhat covered by the pronotum. Pronotum short, rounded, smooth ; 

 transverse incision almost obliterated ; oblique dorsal impressions irregular; 

 the dorsal portion cinereous ; sides with a triangular black spot, interrupted 

 by light spaces ; broadly margined with dull white ; lateral angles tipped with 

 piceous-black. Tegmina short, extending over the second abdominal seg- 

 ment ; margins pale yellow, central portions brown. Abdomen cinereous, a 

 darker line along the sides ; notch of the sub-anal plate very small ; append- 

 ages small, hairy ; the tip of the last dorsal segment strongly bifid, denticulate. 

 The cerci (I use this term for those appendages supplying the place of cerci) 

 slightly bent, bifurcate. Legs same color as abdomen and cranium ; anterior 

 pair quite short; middle pair a little longer; the posterior pair very long, 

 the femur marked with a dark line along the upper angle; tibia slender, 

 spines tipped with brown. Antenna? at least twice as long as the body. 



Length -75 in. ; posterior femur -62 in. ; tegmina beyond the pronotum -1 in. 



Female similar to the male in appearance, coloring and size. Cerci small, 

 hairy. Ovipositor bent, somewhat narrowed in the middle ; brown at the tip. 



Length as in the male. Ovipositor -55 in. 



Bab. Same as A. Stevensonii. Some specimens in each of the species have, 

 on the under side of the posterior femur, about four or five abortive spines, 



1870.] 



