NORTH AMERICAN NEUROPTERA. 267 



straight, three-quarters as long as last segment on 9th ; no dorsal hooks, but on 

 3 to 9 along the median line of segments a flattened pad covered with fine felt, 

 ending on 9th (and much smaller on 8th) in a short, flat, triangular median spine 

 exceeding the apical margin of the segment; sears on 3 to 8 with a black macu- 

 lose streak and three black and polished spots; on 9th and less visible on 1 0th a 

 longitudinal blackish line not reaching base or apex: on 3 to 8 two black trans- 

 versal dots in the middle of segments ; appendages less than half of last segment, 

 pyramidal, sharp on tip, of equal length; laterals a little shorter; the genitals 

 marked; the ventral longitudinal sutures straight, nearer together on 9th, ending 

 on the lateral spines ; lateral spaces as broad as the middle one ; legs short, strong, 

 fringed with long hairs; first legs a little shorter than second, curvate, a strong 

 apical end hook on tibia, claws short, strong, third pair longer, the more flattened 

 femur reaching 4th segment, claws a little longer ; third joint of tarsi nearly as 

 long as the two basals together; lateral margin of abdomen villous. 



The smaller nympha 25 mm. long from South Carolina, collected by 

 Osten Sacken and mentioned by Mr. Cabot, p. 2, has the apical spine on 

 segments 8 and 9, and would well belong to G. palh'dus, were not the 

 lateral spines on 9 very short. 



Prof. Forbes has dredged in Cedar Lake, Illinois, Oct. 16-18, 1882, 

 in very shallow water and caught a number of very young nymphae 

 which belong surely to G. pall id us ; length 8 to 20 mm. ; more villous 

 than the full grown ; shape of body the same but flatter ; occiput nearly 

 straight behind, antennae with fourth joint larger, more globular ; middle 

 tooth on front margin of mask visible ; palpus inside with five to eight 

 teeth ; wing cases only reaching 2d segment ; abdomen sloping gently to 

 tip; 9th segment longer than 8th, the middle spine on apical margin 

 visible ; lateral spines on 7th to 9th segment, the latter ones half as long 

 as 10th segment. 



The principal characters for G. pallidits are the middle tooth in front 

 margin of mask, which becomes blackish in the full grown ; the teeth 

 along the whole inner margin of palpus ; the sloping of the abdomen is 

 continuous and not suddenly stronger after 7th segment ; the middle 

 dorsal spine on apical margin of 9th ; lateral spines only on 7 to 9, the 

 latter one longer ; even the youngest nympha, 8 mm. long, shows those 

 characters, though the wing cases are justly budding and do not reach 

 the end of segment 1 ; the teeth on the palpus are less in number, the 

 lateral spines shorter. 



The nymphae represent four different moults ; those long 8 to 12 mm. 

 have six teeth on the palpus farther distant and more pointed ; those 15 

 to 25 mm. long have seven teeth near together, but straight on tip and 

 the inner angles sharper and rejected ; the apex of the teeth somewhat 

 notched; those long 27 mm. with eight teeth, more pointed; the full 



