Affinities of Pteronarcys regalis. 449 



In some manuscript notes, which he has favoured me with, he has designated 

 the perfect insect the Drummer {Perla sonans, Barnston's MSS.). He says 

 that, " when confined upon a table it sometimes makes a drumming noise, 

 by beating on the wood with the end of its abdomen, whence I have given 

 it its specific name, as I have not observed this done by any other species. It 

 appears after the Pteronarcys regalis, and is more numerous. The perfect 

 insect prefers the shade in the heat of the day. The sexes pair like the Grass- 

 hopper, and their union lasts for some time. Its habits separate it much 

 from Pteronarcys and Phryganea. The larva and nymph are aquatic and 

 carnivorous. The cast-ofF spoil of the nymph is generally found under 

 stones on the banks of rivers. The larva is very active in the water, and 

 frequents the clefts and cracks in decayed stumps of trees, into which its 

 flattened shape permits it to enter with facility. It is a favourite food of the 

 trout." 



The Pteronarcys, according to Mr. Barnston's observations, is as inferior 

 to this Perla in its habits of life, as I have shown it to be in its organization. 

 In its pupa state it resides constantly at the bottoms of streams, and the per- 

 fect insect comes forth at an earlier period, and at a lower temperature of the 

 season than Perla. Some other Canadian Perlidoe, which are more nearly 

 allied to it in structure than Perla ahnormis, come forth at about the same 

 time, and as it is doubtful whether these species have yet been described, I 

 shall characterize them from specimens given by Mr. Barnston to the British 

 Museum, and add some observations on the habits of each from notes made 

 by that gentleman. 



The generic characters 6f Pteronarcys I propose to correct as follows, in 

 accordance with its structure. 



Genus Pteronarcys, Newm. 



Chab. Gen. Segmenta thoracica etiara in Imagine branchiis externis prasdita, Ala 

 magnas, reticulatae. Palpi maonllares labialibus multo longiores, 5-articuIati ; articulis 

 2 basalibus brevibus, reliquis elongatis, externe dilatatis. Mandibulce parvae, obtusae. 

 Segmentum abdominale octavum in mari processu longo ventrali munituni, in foemind 

 paulo evolutum vel bifidum. 



The following new species has recently been brought by Mr. Hartweg from 



California. 



3 N 2 



