NORTH AMERICAN CADDIS-FLY LARVZ. 
The spacing-humps are larger, and the abdominal segments less 
constricted, giving the larve a less scalloped appearance. 
DisTINCTIVE CHARACTERS OF THE Pupa:.—The pupe of Neu- 
ronia may easily be distinguished from those of Phryganea by 
their short rhomboidal mandibles, almost as broad as long. 
DESCRIPTION OF THE CasE.—The cases of the known species 
of North American Neuronia are easily distinguished from any 
other known cases. They have the form of very slightly bowed 
cylinders, varying in length, but always much longer than the body 
of the larva, and tapering very little, if at ali. The cylinders are 
composed of a series of rings placed end to end. Each ring is 
made of broad quadrilateral sections of leaf. The rings are neatly 
fitted without overlapping, in the cases of old larve. Young larve 
sometimes leave the caudal ends of the leaf fragments protruding 
in long strips. 
The cases of the larve of American Neuronia differ remark- 
ably from those of the European members of the genus. In 
Europe the cases are described as spirally built, like those of Phry- 
ganea. When a careful study of the adults and larve from Amer- 
ica and Europe is made, it may be found that there are generic 
differences of structure correlated with this difference of habit 
in case-making. _ 
K&ryY TO THE SPECIES OF NEURONIA LARVA. 
A. Mesonotum without chitinous plates. Frons with a dark 
mark on each side, not connected to form a U-like pattern. 
—WN. postica. 
A.A. Mesonotum with two minute chitinous plates near its 
cephalic margin. Frons with the dark marginal marks con- 
nected behind to form an irregular U-like pattern. 
B. Robust larve measuring 30 mm. when mature. Markings 
dark.—N. pardalis. 
B.B. Less robust larve, not exceeding 20 mm. in length. Mark- 
ings less prominent than in N. pardalis.—N. stygipes. 
NEURONIA PARDALIS. 
Hasrtat.—The larve have been taken only in Argus Brook 
and in the old mill-race, at McLean, but adults on the wing in 
Michigan Hollow and in Bear Swamp indicate that the species 
also breeds in those localities. 
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