154 GEO. H. HORX, M. D. 



signing any reason, at the same time describing new species which sliould 

 not be included in Pseudomorpha. The two genera, SUpliomorplut 

 and Sphalhmoi'pha, can hardly be considered as distinct, the charac- 

 ters separating them being hardly of more value than as a means of 

 defining generic groups. The whole subject has yet need of a revision, 

 and it is to be hoped that those entomologists who have a full series of 

 species accessible will determine their synonomy, and relieve them from 

 the partial confusion in which they are at present found. 



The habits of these insects are remarkable. Both our North Ameri- 

 can species live on flowers, and are very agile, while that from South 

 America and those of Australia appear to live under bark. 



For an opportunity of examining a small series of these insects, I 

 am indebted to Dr. Leconte, to whom all the species in the Cambridge 

 ^Museum were sent by Prof. Agassiz for study and identification. 



On AMPHIZOA INSOLENS, Leconte. 

 BY GEO. H. HORN, M. D. 



It is not expected that anything new will be written in the present 

 paper, as the insect has been fully described by Dr. Leconte, (^Froc. 

 Acad, vi, p. 227.) and its systematic position ably discussed, while Dr. 

 tSchaum {Insccten DeutschUinds) reviews the work and expresses a dif- 

 ferent opinion regarding its relationships. As it is very desirable to 

 have all difficulties removed and differences of opinion adjusted, it has 

 been thought advisable to pi-esent tlie subject anew to systematists, in 

 order that the end may be reached. With this view, wood-cuts, care- 

 fully drawn, have been prepared, to illustrate the various external 

 parts. 



As the habits of this insect have been fully exposed {Proc. Ent. Soc 

 J*h)l., Vol. vi, p. 289), it will be unnecessary to reiterate in the pre- 

 sent paper, except to state that they live as do the ParnidtB, adhering 

 to stones under running water. They are entirely sub-aquatic, and 

 have never been found on land. It was my good fortune to capture a 

 fine series of this insect while traveling in north-eastern California, 

 among the streams tributary to Pit River, itself the larger fork of the 

 Sacramento. Though still a rare insect in collections, it has been 



