71 



Illinois is based on an erroneous determination. The only 

 nymphs of this species known to us were found by Mr. Needham 

 in New York. It abounds in all the streams about Ithaca, trans- 

 forms in May by thousands, and scatters to the woods. Many 

 imagos were seen by him foraging about the borders of upland 

 woods and going to rest at night among the branches of trees, 

 but he did not observe their breeding habits. 



Transformation takes place generally before daylight and 

 within a few inches, or at most a few feet, of the water's edge. 



The nymph measures 29 mm.; abdomen, 18 mm.; hind 

 femur, 7 mm.; width of head 5.5 mm., of abdomen 8 mm. Body^ 

 very flat and hairy; legs and antennae and lateral margins of 

 head very hairy. Head depressed and wedge shaped. 



Labium short; mentum squarish beyond the narrowed 

 basal third; median lobe nearly straight; lateral lobes very 

 arcuate, ending in a distinct hook on the inside of which is a 

 very broadly pyramidal tooth; proximally the lateral lobe bears 

 on its inner side a series of 7 to 9 short, broad, slightly recurved 

 teeth; movable hook long and strong. 



Abdomen lancet shaped; scars above and ganglion pockets 

 beneath very plainly marked; segments 2 to 8 about equal in 

 length, 9 one half longer, 10 half as long as 9; dorsal hooks 

 reduced to broad median swellings on segments 2-9, not hooked 

 nor pointed; lateral spines on 6 to 9, those of 9 about one half 

 as long as 10. Superior and inferior appendages one third 

 longer than 10, laterals a little shorter. 



4. GoiitpJius qi(((driroIorW?i\sh. 



This imago is seldom captured in Illinois. The nymph is 

 unknown. Walsh's examples were taken at Rock Island. Mr. 

 Adams took the imago at Bloomington June 23. Kellicott 

 made three captures in Ohio, May 20 to June 15; Williamson 

 found one June 26 ; and it is also on record from Indiana, Michi- 

 gan, and Massachusetts. It rests, according to Kellicott, on 

 rocks projecting from rapids, or on the banks near by the 

 most rapid parts of large streams. 



