SOMATOCHLORA 193 
A fine medium sized species. Face brownish; labrum, top of frons, vertex 
and occiput dark brownish with metallic reflections. Thorax metallic; lateral 
yellow stripes wide and straight. Legs black, first femora paler externally. 
Abdomen dark brown; segment 2 with apical and median annuli and pale lateral 
spot; 3 paler basally with paired dorso- and ventro-lateral triangles (in 9 con- 
tinued to segment 7, decreasing in size); 9, 10 and appendages yellow beneath. 
157. Somatochlora elongata Scudder 
Scud. ’66, p. 218: Mtk. Cat. p. 180: Walk. ’25, p. 70: Garm. ’27, p. 220. 
Length 57 mm. Expanse 65 mm. N. B. to Mass. and Md. 
A slender, dull greenish, clearwinged species. Face metallic. Anteclypeus 
and sides of frons yellowish. Thorax dark metallic with a thick coat of whitish 
brown hairs. Lateral thoracic pale spots light yellow, clearly defined; the first 
slender and straightish, the second half as long and ovoid. Legs brownish. 
Wings hyaline with a faint basal yellowish tinge; stigma black. Abdomen brown. 
Segment 2 with three pairs of lateral pale spots, sometimes more or less confluent, 
and with an apical annulus; 3 with a pair of small basal dorsal spots; remaining 
segments greenish black. 
158. Somatochlora semicircularis Selys 
Selys ’71, p. 295. Mtk. Cat. p. 182: Walk. ’25, p. 145. 
Syn: nasalis Selys 
Length 49 mm. Expanse 63 mm. B. C. to Calif. and Colo. 
Frons above and in front black with metallic reflections; vertex the same. 
Labrum and postclypeus black; anteclypeus yellowish. Occiput dark brown. 
Thorax metallic green with two lateral yellow spots, becoming obscure with age. 
semicircularis williamsoni 

Legs black. Wings hyaline, hind pair with a slight basal flavescent tinge. Ab- 
domen greenish black; segment 2 with two pairs of lateral spots and an inter- 
rupted apical annulus; 3 with a pair of basal dorsal spots and a ventral lateral 
streak; 5 to 8 sometimes with a small lateral spot. 
