ORTHOPTERA OF NOVA SCOTIA. -PIERS. 269 



The stridulation or call of this very common locust 

 sounds like the lisping syllables thru, thru, thru, repeated 

 from about seven to ten times, and lasting altogether three 

 or four seconds. It is a soft, dreamy, lulling sound of the 

 country, and quite characteristic of a quiet, hot forenoon 

 in August and September, and is still heard in October. The 

 insect may be seen producing the notes by raising the hind 

 legs and grating the thighs against the outer surface of the 

 wing-covers. These notes are heard from about the beginning 

 of August, or perhaps earlier, and as long as the adults are 

 about; but the sound is quite faint at the end of the season, — 

 in fact the species calls most frequently during hot sunny days. 

 The male is a fairly active and noiseless flier, but the female 

 usually escapes by leaping. 



Group Epacromise. 



Key to Nova Scotian Species of Mecostethxjs. 

 a. Scapular area of wing-covers loith a pale (yellow) streak; intercalary vein 



of male wing-cover with very obscure, low teeth 8. lineatus, p. 269. 



aa. Scapular area of ■ wing-covers without a pale streak; intercalary vein of 



male with minute, sharp, elevated teeth 9. gracilis, p. 271. 



8. Mecostethus lineatus (Scudder). 



Mecostethus lineatus. Gooderham, Proc. Ent. Soc. N. S. 

 for 1916, 25, 27 (1917); Kings and Yar. Cos. 



Description. — Foveolse of vertex visible from above; pronotum with 

 three distinct carince, the median rather high and sharp, plainly cut by 

 principal sulcus somewhat in front of middle; lateral carina? distinctly div- 

 gent behind; prozona (front part of pronotum) shorter than metazona (hind 

 part); intercalary vein of male wing-cover wnth very obscure, low teeth; wing-covera 

 and wings well developed, surpassing end of femora by about one-third of 

 tibia. 



Colour. — Nova Scotian female. General colour brownish with yellow 

 markings; beneath yellowish-green; wing-covers ^^ith a pale yellowish streak. 

 Head and pronotum dark vandyke-brown, the latter liver-brown on the 

 lateral lobes; labial region Ught olive-buff. Pronotum liver-brown on lateral 

 lobes, Ughter on disk; under parts of prothorax oil-green. Abdomen dark 

 clove-brown (nearly black) above and on sides, beneath light apple-green; 

 a pale yellow, somewhat broken Une along each side of uppei part of abdomen, 

 and three similarly coloured spots on sides of abdomen. A distinct, pale 

 canarj'-yellow narrow line extends from near upper part of eye, along side of 

 head, and continues, somewhat broader, on the lateral carina? of the pronotum. 

 A pale, canary-yellow dash, rather broad, extends diagonally across posterior 

 part of cheek and anterior part of pronotum. Wing-covers pale cinnamon- 

 cjlour, darker at base and on sides. From the base a distinct pale canary-yellow 

 line extends near the lower {anterior) edge until it reaches about the middle of 

 the length of the wing-cover; the apical part of this line is broken up and so 



