HEMIl'TEBAlIOMOPTEBA APHIDES. 2<>5 



less than half-way to tin- hind margin, bent at the first furcation, and passing 

 exceedingly close to the stigmatic vein, the upper branch of the final fork 

 in direct continuation of the main stem. Stigmatic vein arising at about 

 one-third the distance from the first to the second furcation of the cubital 

 vein, very longitudinal, so that the stigmatic cell is rather slender and very 

 long, fully two-fifths the length of the wing. Legs slender, the femora tol- 

 erably stout, the fore and middle legs of equal length in all parts. 



Length of body, 3.5 llim ; antennae, G.5 mn ' ; wings, 5""" ; fore legs, 3.9 mni ; 

 femora, 14""": tibia? and tarsi, 2.5" 1 " 1 ; middle legs, '5. 9""" ; femora, 1.4 mi "; 

 tibia; and tarsi, 2.5"""; hind legs, 5.1"""; femora, 2.25"""; tibist and tarsi, 

 2.85""". Another specimen had a body 4.75""" long, with wings nearly 

 fi.5""" and hind femora 2.5 mm long. 



In honor of Mr. William Ilealy Dall, the malacologist, well known 

 also for his studies of fossil invertebrates. 



Florissant. Two specimens, Nos. 9135, and from the Princeton Collec- 

 tion I.IO'.H. 



6. APHIDOPSIS EMACIATA. 



This diminutive species is represented by a single specimen with 

 spread wings, without antenna' or legs. It has an expanse of only six mil- 

 limeters or less. The head and thorax are uniformly dark, the abdomen 

 uniformly light colored. The wings are as long as the body and more 

 than three times as long as broad. The postcostal vein is broad, but not 

 darkly pigmented, as usual, and the stigma large and distinct. First oblique 

 vein straight, parting from the postcostal at an angle of about seventy-five 

 degrees ; the second oblique also straight, parting at an angle of about 

 forty-five degrees, but though the wing is slender, the discoidal cell, narrow 

 at base, is several times as broad on the hind margin as at base. Cubital 

 vein arising about midway between the first oblique and stigmatic veins, 

 and twice as far from the second oblique vein as this from the first ; it 

 iir>t forks at some distance from the base, and is strongly arcuate, approach- 

 ing much nearer the stigmatic than the second oblique vein. Stigmatic 

 vein arising very far back, almost to the first furcation of the cubital vein, 

 and, reaching down far into the wing at the start, it gives a very large 

 stigmatic cell, almost half as long as the wing. 



Length of body, 2.5'" m ; fore wings, 2.5""". 



Florissant. One specimen, No. 6405. It conies from the uppermost 

 layers. 



