(we 
THE CANADIAN ENTOMOLOGIST. 
me to be the best division which has been attempted ; but the number of 
species is not yet large enough to make its division necessary as a matter 
of convenience, and therefore it appears to me best to let it stand until the 
study of a large number of species in all stages of growth shall make a 
natural division possible. - 
The species differ in the szze of the labial palpi as well as in their 
clothing. In some, the vertex is very slightly roughened, shewing an 
approach to Ornzx ; and in some, the scales at the sides of the vertex 
project over the base of the antennæ, almost forming small tufts. 
There is also considerable difference in the larval habits of the difier- 
ent species. Some, perhaps, do not mine ieaves at any period of their 
lives, or for a very short period, if at all. Others mine them only for a 
short period. When leaving the mine, they become external feeders, rolling 
the leaves of their food plants into various forms. Others again are 
miners during their whole larval existence, and of these, some never leave 
their first mine until they do so to become pupz, whilst others frequently 
leave their old mine to construct a new one. Some pupate under a dense 
but semi-transparent silken coverlet or web, whilst others make a small. 
silken cocoon or zzdus,and one species known to me pupates in the mine. 
In such a genus, it is worse than useless to encumber science with a 
multitude of generic names until a sufficient study of many species has 
made a natural division practicable, or at least until the accumulation of 
species makes an artificial division necessary. 
I. Gracllaria robiniella. 
Parectopa robiniella Clemens. Proc. Ent. Soc., Phila., 1803, p. 4. 
Dr. Clemens erects this genus for his P. lespedezefoliella, in the Proc. 
Acad. Nat. Sci., Phila., 1860, ~. 209, and afterwards describes this species 
as above stated. Gracilaria (Proc. Ent. Soc., Phila., 1863, page 9), as 
limited by him, is Zeller’s section A, in which nine veins are given off from 
the discal cell. This insect belongs to the division in which there are only 
eight, and its neuration only differs from that of G. salicifoliella, n. sp., in 
having one of the veins, from the apex of the cell, furcate mear ifs origin, 
whilst G. salicifoliella has it furcate at its origin, and slightly bent. Nor is 
the head any more tufted than in Sa/icifoliella, and some other Gracilaria 
which have long loose scales on the vertex. As before stated, Dr. Clemens 
was mistaken in the statement that the maxillary palpi are not visible, and 
it is therefore as clearly a Gracillaria as any of the other small species 
