1873.] 285 [Hagen. 
and the type is dry; but I observed that those parts are somewhat 
changed in shape by drying, in a female of Pt. californica from Mr. 
M’Lachlan’s collection sent over for examination. Nevertheless, as Mr. 
M’Lachlan insists that Pt. biloba is a different species, we must wait for 
a more detailed description. I have never seen in any collection, 
here or abroad, any specimen, except the type of the former from 
Trenton Falls, of P. biloba or P. californica, from the United States 
east of Utah. 
ITI. Pteronarcys nobilis Hag. Syn., 15, 4. 
Dark fuscous above ; the spots outside the posterior ocelli black, 
shining; basal border of the antenne very narrow, a little broader 
in the middle; prothorax a little broader than the head, sides 
straight, front and hind border a little arcuated; the angles sharp- 
ened; the yellow median line broader at the ends; antenne and legs 
dark brown, knees yellowish; body below orange in tke middle; 
sete dark, a little paler at the base; wings smoky, veins dark, 
with clouds. 
Male. The ninth ventral segment black, shining, inflated and 
elongated toward the set, the tip notched; last dorsal segment 
with two black, horizontally placed appendages, somewhat thicker at 
the rounded tip; penis as in P. regaks, but I cannot see it from 
above. 
Female. The eighth ventral segment straight at tip, perhaps a 
very little produced in the middle third; there are no appendages 
(as I described with a? in my Synopsis), but the parts are not in 
good condition. 
Length, with the wings, 31-34 mm.; expanse of wings 55-66 
mm. I possess a pair from New York, formerly in Winthem’s col- 
lection, and I examined: a male from Trenton Falls, N. Y., in the 
British Museum. 
A male from Knoxville, Tenn., in my collection, belongs, perhaps, 
to a different species; but having seen only this one specimen, its 
abdomen also not in good condition, I should not like to decide this 
question. It differs in being of much darker color, especially the 
wings, which are smoky black, except the apical third of the hind 
wings, which is dark gray. The orange patch on the under side of 
the abdomen is much smaller, and is only indicated on the thorax ;, 
the knees are dark; the prothorax is smaller in front, the sides more 
oblique, the hind border more arcuated, the angles more sharpened. 
The anal parts seem to be similar, so far as can be observed. ‘The 
size is larger. Expansion of the wings 66 mm. 
