THE CANADIAN ENTOMOLOGIST. 183 



Op/iiogoinphus caroliis, n. sp. Male and female. — Ithaca, N. \. 



Length, 40-42 mm,; abdomen, 28-31 ; hind wing, 24-26 



Greenish-yellow and blackish-brown. 



Face greenish-yellow, paler toward the mouth. Rear of frons and vertex except 

 the rear, lilack. Occiput yellow, its slightly convex margin ciliated with long black 

 hairs. In the female there is generally in front of the margin a pair of black-tipped 

 spines, whose various development is shown in plate, tigs, i to 4. These sometimes 

 occupy the margin which then becomes notched between them. Rear of eyes l)lack 

 above, mottled \vith paler below. 



Prothorax blackish, its liind lobe with a median twin spot and a lateral spot each 

 side yellow. 



Thorax greenish, its dorsal stripes fused, enveloping the carina and forking with it 

 above to meet the humeral, Antehumeral stripe isolated above, sometimes meeting the 

 humeral near its upper end, but well separated through most of its length by a narrow 

 greenish line. A partial l^rown line on the ist lateral suture and a narrow complete 

 one on the 2nd, 



Legs black, front femora paler l:)elow. 



Wings hyaline, often Havescent at base, costa black ; stigma cinereous. 



Abdomen cylindric, a little narrower in its middle two-thirds, superiorly blackish 

 with a maculose yellowish middorsal line of lanceolate spots on segments 3 to 7, of 

 quadrangular basal spots on 8 and 9. Inferiorly, whitish with fuscous apical spots on 

 most of the segnientSj Ten yellow ; fuscous at both ends. 



Male appendages : superiors, longer than the loth segment, cylindric ; seen from 

 above, with acute apices divergent ; seen from side, fusiform, with truncate apices, 

 denticulate beneath for one-third their length. Inferior appendage (see plate, fig. 7) 

 bifid by a rounded notch, each branch somewhat flattened with four distal angles 

 (as shown in the figure) or sometimes with only two (merely obliquely truncate); 

 always with an upturned tooth at the outermost angle, sometimes with another at the 

 innermost. 



The genital hamules are shown at fig. 6 in the plate. These appear to be quite 

 constant in form. 



Female appendages fuscous, longer than 10 ; anal segment as long as the 10th. 

 Vulvar lamina about as long as the 9th segment ; bifid except basal fourth, the branches 

 enclosing an oval notch beyond which their incurved apices meet and then abruptly 

 separate in short, oval, divergent points. 



Described from more than seventy bred specimens (some of which 

 will find their way into the collections of all my correspondents), from a 

 single 9 in the Cornell University collection, and from five specimens 

 captured in May by Mr. Chester Young and Mr. J. O. Martin. I 

 collected nymphs in October which emerged on my table in March. It 

 was easy to collect the nymphs by hundreds in April, and in May the 

 banks of the waters they frequented were fairly covered with exuviiw, 

 Yet, outside of my breeding cages I saw but one live imago, notwith- 



