THE CANADIAN ENTOMOLOGIST. 163 



moreover, a common one here and is the only Enallagma of the 

 region whose nymph has not been reared (except the rare E. ebrium) . 



Nymph (Figs. 9, 10), long and slender, eyes very prominent 

 laterally, their postero-lateral margins forming with the sides of 

 the head a marked excavation. Hind angles of head with numer- 

 ous slender setae, rounded, but very prominent and narrower than 

 the median concavity. Labium with 3 mental setae: lateral seta:' 

 5; lateral lobes, before the end-hook, with three well-marked 

 teeth, preceded by a feebly denticulate, almost truncate, margin. 

 Abdominal segments 2-7, with prominent postero-lateral angles. 

 Gills large, broad lanceolate, widest at the distal third, with a 

 transverse median joint; basal half dark, except at the base; apical 

 half whirish or grey, except a broad, dark anteapical band. 



Colour brown (alcoholic, probably greenish in life), sides of 

 head and thorax with a pale longitudinal band between two dark 

 bands, the most ventral of which passes dorso-caudad to the bases 

 of the front wing-cases. There are usually also a few dark spots 

 on the head and thorax. Abdomen rather dark brown, almost 

 uniform. Legs pale, femora with a very narrow, but usually well- 

 defined, dark ring at the distal fourth. 



Length of body 13 (contracted) to 18 (extended); gills .5-6.5; 

 hind-wing 4.3-5; hind femur 3.5; width of head 3.25-3.4. 



Boyeria grajiana Williamson. 



The dark-coloured nymphs of this species are found rather 

 commonly under stones, along more or less wave-bea;ten shores or 

 wherever there is a perceptible current. Full-grown specimens 

 were collected on and after June 4, 1912, the first adult emerging 

 in the laboratory on July 14, followed by several otheis during the 

 succeeding fortnight. 



As the nymph of Boyeria vinosa was described before B. gra- 

 jiana had been recognized as a distinct species, it is impossible to 

 be certain whether the descriptions all refer to B. vinosa or not, 

 but Needham's description* belongs, with scarcely a doubt, to that 

 species. 



We have reared a number of nymphs of B. grajiana and col- 

 lected many exuviae as well as nymphs in several localities. We 

 have also received a series of exuvia; of a Boyer ia from the Shawa- 

 *Bull. 47, N. V. State Museum, p. 4(3'), 19;)1. 



