302 



This species cannot be referred with propriety to any one of the 

 eighty-five British genera of Geometridse. Hipparchus Leach, Hemt- 

 tliea Duponchel, and Chlorissa Stephens, all agree with it in the wings 

 being green, but it differs from the first in the hind wings not being 

 denticulate, from the second in the palpi not being short, and from 

 the third in the c? antennse being distinctly bipectinate. I am not 

 aware, either, that any described genus of Geometridee has the larva fur- 

 nished with the remarkable lateral appendages met with in this insect, 

 or the hind tibise of the c? imago furnished, as in this insect, with 

 large fan-like brushes. Such brushes, indeed, occur in the front 

 tibiae of many Pyralide genera, e. g. Macrochila, Pechipogon, and 

 Paracolax, commonly called " fan-footed moths," and I notice them in 

 five or six U. States Pyralide species in my collection. In another 

 green Geometride species in my collection, which manifestly belongs 

 to a distinct genus, there is no such fan-like brush on the cf hind 

 tibise, though, as in several other genera in this family, there is a small 

 one on the c? front tibiae. 



DIPTEKA. 



The only known Tabanide larva, as I am informed by Baron Osten 

 Sacken, has been described by De Geer, and was terrestrial. (See 

 Wesiw. Intj:, II., p. 541 and fig. 128, 9.) The following is aquatic, and 

 the imago obtained from it belongs to the genus Tabanus, but is in 

 too bad condition to be specifically determined, having remained 

 many weeks unattended to in the breeding-jar. I have, on many differ- 

 ent occasions, found this larva amongst floating rejectamenta. On 

 one occasion I found six or seven specimens in the interior of a float- 

 ing log, so soft and rotten that it could be cut like cheese. Once I 

 discovered a single specimen under a flat, submerged stone, in a little, 

 running brook. And finally, I once met with one alive, under a log, on 

 a piece of dry land which had been submerged two or three weeks before, 

 whence it appears that it can exist a long time out of the water. I 

 had, on several previous occasions, failed to breed this larva to matu- 

 rity, and the only imago I have was obtained in 1861, from larvse, 

 which, suspecting them to be carnivorous from the very varied stations 

 in which they had occurred, I had supplied with a number of fresh- 

 water mollusks, but the habits of which, in consequence of having been 

 away from home, I was unable to watch. On Sept. 2d, 1863, 1 found a 

 nearly full-grown larva amongst floating rejectamenta, and between 

 that date and Sept 23d, he has devoured the mollusks of eleven uni- 

 valves (^Gen. Planorhis) from one-half to three-fourths of an inch in 

 diameter ; and on three separate occasions I have seen him work his 

 way into the mouth of the shell. In this operation his pseudopods 

 were energetically employed, and I found, on cracking the shells 



