PLECOPTERA NYMPHS OF NORTH AMERICA 111 
pharynx broadly rounded and normally extended beyond the 
olossae. 
The nymphs of this species are herbivorous and may be found 
in small upland streams where they usually occur in leaves and 
debris. : 
Ithaca, N.Y. 
Genus ALLOCAPNIA Claassen 
Allocapma Claassen, Annals Ent. Soc. Amer., vol. 21, 1928, p. 667, to replace 
Capnella Claassen, preoccupied. 
The nymphs of this genus are most readily recognized by the 
Shape of the hind wing pads. It is the only genus in which the 
anal field of the hind wing extends almost to the tip of the wing, 
giving the wing pad a broadly triangular shape. The front wing 
pads are slender, set far apart at the base, and lie parallel to the 
body. The nymphs when fully grown seldom measure more than 
8 mm. in length, exclusive of antennae and ecerci. 
General color yellowish to dark brown. 
Head as wide as, or slightly wider than pronotum. Three oeelli, 
the hind ones about twice as close to the eyes as to each other. An- 
tennae long and slender, about half as long as body, and made 
up of about forty-five to forty-eight segments. 
Pronotum subquadrate with rounded angles ; somewhat widened 
posteriorly ; surface moderately hairy ; marginal groove noticeable 
along the anterior margin. Wing pads present in all species except 
in the males of A. viwpara where they are either absent or ves- 
tigial. Legs rather short; femora and tibiae covered with hairs 
and with a sparse fringe of long hairs on the outer margins; first 
segment of tarsus about twice as long as second; third about twice 
as long as first and second combined. 
Abdomen cylindrical. The sexes are readily distinguishable. 
In the male, the tenth tergite is produced into a long triangular 
protuberance (supra-anal lobe) which is directed slightly up- 
wards. In the female, the tenth tergite is only slightly produced 
into a broadly rounded lobe. Cerci long and slender, normally 
about half as long as body, composed of about twenty-five to 
thirty segments, each segment ending in a whorl of long hairs. 
Gills absent. 
The mouth parts are of the herbivorous type, and their struc- 
ture is so similar in the different species of the genus that they 
apparently are of little taxonomic value in separating the species. 
Very little detailed work has been done to determine the exact 
