101 



a degraded form. It lives in the burrows of AnthopJiora sponsa, 

 a mason-bee building in clay-banks, and probably spends most 

 of its time in the bee-gallery. The triungulin has not been 

 discovered, but the other forms of the larva exhibit the ordi- 

 nary characters of the family. 



Another discovery by Mr. Riley is that of the curious egg- 

 mass of Corydalus coi'nutus, an insect extremely interesting 

 from its relationship to carboniferous types found both in 

 this country and in Europe. The larva and pupa have long 

 been known, but the place of deposition and the nature of its 

 eggs have remained unknown ; or rather, eggs of another in- 

 sect, which Mr. Riley believes to be a Belostoma, have been 

 accredited to it, on the authoi-ity of the late Mr. Walsh. Hal- 

 deman's figures of the eggs have been very generally over- 

 looked. As it now appears, tiie eggs are laid in oval masses, 

 upon leaves of trees overhanging the water, or upon rocks ; the 

 mass is composed of two or three thousand eggs covered with 

 a common white or cream-colored albuminous secretion. Tiie 

 young leave the egg-mass at night and in company. 



Of precisely similar interest is the allied genus Pteronarcys, 

 living specimens of which Dr. Hagen has studied to good pur- 

 pose. He observed that the male taps u])on the surface on which 

 it is seated, with its abdomen, as Barnston had observed in the 

 case of another Perlarian. He witnessed also the remarkable 

 union of the sexes. Oviposition he did not see, but the eggs, 

 probably dropped in the night, were laid in little heaps in the 

 grass or in the water. He studied the curious gills with which 

 Newport has made us acquainted, but which in life are more 

 bag-shaped, with the fringe less widely spread than preserved 

 specimens would lead us to suppose. No motion was seen 

 in these gills after the most careful observation ; and the 

 whole appearance of the gills, on internal examination, was 

 that of an organ unfitted for breathing, although the tracheae 

 were very abundant in their immediate vicinity ; on the 

 other hand the abdominal spiracles, at least as far as the 

 seventh segment, were perfectly formed for respiration. More- 

 over the creatures not only did not seek the water, but on 

 falling into it, or being placed in it, they scrambled out with all 



