perlid;e. 591 



the transverse veins few in number, almost absent, and there 

 is no basal space in the posterior wings. The palpi ai'e seta- 

 ceous, the last joint being shortest. Isopteryx Cydippe New- 

 man is pale yellow and immaculate. 



Gapnia is known by the wings being veiny, with the trans- 

 verse veins ver^^ few and regular ; the anal area of the posterior 

 wings is large, plicate, and the palpi are filiform, with the last 

 joint ovate, longer than the preceding one, and there are two 

 setae. Gapnia pygmcea Burm. is shining black, with gr.ay hairs. 

 It is common in New York in Februarj^, according to Dr. Fitch. 

 The species of Tceniopteryx have the wings inrolled and reined, 

 with the transverse veins A-ery scarce, rather regular ; the anal 

 area of the posterior wings is large and plicated ; the palpi are 

 filiform, with the last joint ovate. There are no abdominal 

 setse, and the tarsi are divided into three long equal joints. 

 They fly early in spring and late in the autumn, and south- 

 wards, during the winter. T. frigida Hagen is black, with 

 grayish hairs, with a gray band on the middle and another at 

 the apex of the nearly transparent wings. In Nemoura the 

 wings are veiny, flat, and the transverse veins are few, very 

 regular, the veins of the pterostigma forming an X. The anal 

 area of the posterior wings is large and plicate, and there are 

 no caudal setae. The males are smaller than the females, with 

 shorter wings. N. albidipennis Walker is piceous, shining, 

 with whitish wings. The genus Leuctra differs from Nemoura 

 in the wings being rolled in when at rest. L. tenuis Pictet is 

 fuscous, with three elevated lines on the disk of the thorax. 



Under the name PalcB02'>terina, Scudder has described a 

 group considei'ed by him as a distinct family which comprises 

 but three fossil species discovered in the Carboniferous forma- 

 tion at Morris, Illinois. The fragments of the first species 

 found were described by Professor J. D. Dana in 18G4, under 

 the name of Miamia Bronsoni (Plate 1, fig. 1, the dotted lines 

 represent the parts restored by Mr. Scudder). He states 

 that this insect "while Neuropterous in wings, closely ap- 

 proaching the Semblids, has broad costate femurs, and even a 

 large spinous joint to the anterior legs, peculiarities which 

 seem to be almost inconsistent with the Neuropterous type. 



