198 THE CANADIAN ENTOMOLOGIST. 



the expanded distal part, and just before the latter, it is narrowed 

 to about one one-sixth of the width at the base of the lateral 

 lobes, widening towards the hinge to about twice this breadth. 

 Mental setae normally 5, occasionally 6 on one side. Lateral lobes 

 similar to those of disjunctus, lateral setae 3. 



Lateral spines on segments 5-9, of small size, those on 5 

 usually a little longer than in uncatus. Spinules on lateral 

 carinae of 9, 10-14. usually 11-13. Ovipositor of moderate size, 

 the apex and styli reaching the hind margin of segment 10. The 

 longitudinal series of minute hairs is present on the ventro-lateral 

 edges of the valves. Gills slender, gradually tapering from the 

 proximal third, the breadth at the distal third being about three- 

 fourths or three-fifths that at the proximal third, apices bluntly 

 convexo-acute. 



The coloration is quite similar to that of uncatus. Some 

 specimens are very distinctly marked, the bands on the gills being 

 very conspicuous and sharply defined. 



Length of body 19-21 mm.; labium 3.6-4.0 mm.; outer wing- 

 pad 4.5-5.5 mm.; hind femur 4.5-5.13 mm.; gill 8.5-9.0 mm.; ovi- 

 positor 1.9-2.0 mm. 



Lestes vigilax Hagen. 



Although I have bred this species several times at Go Home 

 Bay, where the nymphs are plentiful, I have at present only three 

 exuviae from reared specimens and one immature nymph from that 

 locality and four exuviae from Old Forge, N.Y., received from 

 Professor Needham. 



They are readily distinguished from other species by the 

 characters given in the key. 



Nymph. — A slender nymph, similar in .form to that of 

 rectangular is. 



Labium relatively short, not extending behind the bases of 

 the hind coxae and in one exuvia only to the middle coxae; some- 

 what abruptly expanded in its distal part, which is about one- 

 third to two-fifths of its entire length, narrowed at the middle to 

 about one-seventh to one-fifth of the apical breadth, and widening 

 towards the hinge to about twice the middle breadth. Mental 

 setae 5 (rarely a small sixth on one side). Inner part of lateral 



