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XVI. On Gracilaria, a Genus of Tineidae. By H. T. 

 Stainton, Esq. 



[Read January 6th, 1851.] 



The genus Gracilaria forms a portion of an exceedingly natural 

 group, the other genera included in the group being Coriscium 

 (which differs from Gracilaria only in the palpi having a tuft be- 

 neath), and Ornix (which has the head rough). The whole of 

 this group are readily recognized by their long filiform maxillary 

 palpi, and by the thickness of the middle pair of tibiae. The per- 

 fect insects when at rest have a peculiar mode of sitting, by which 

 they may be at once known ; they sit with their long narrow 

 wings closed over the back, with the head raised, the body of the 

 insect forming an angle of at least 30° with the surface on which 

 it rests ; the antennae turned backwards, under or over the 

 wings. 



The essential characters of the genus Gracilaria are, head and 

 face smooth ; palpi thin, recurved, the terminal joint pointed ; 

 maxillary palpi long, thin and projecting ; antennae as long as the 

 anterior wings, or nearly so, slender, not enlarged at the base ; 

 anterior wings long and narrow, with long cilia ; posterior wings 

 long and narrow, lanceolate, with long cilia ; middle pair of tibiae 

 much thickened, with hairy scales. 



The larvae of all the species are probably, when young, leaf- 

 miners, some continue always so ; those of most of the species, 

 on attaining a certain age, roll up portions of the leaf generally in 

 the form of a cone ; of this cone they mostly eat the inner sur- 

 face, thus discolouring it, and betraying their habitation. Some 

 species change to the pupa in the cone formed by the larva, but 

 I doubt whether this is most frequently the case. The larva of 

 Auroguttella leaves the cone, and rolls up a leaf of the plant on 

 which it feeds {Hypericum perforatum) in the form of a cigar. 



The genus Gracilaria may be divided into two sections, by the 

 number of veins arising out of the discoidal cell. In Section A. 

 there are nine veins, in Section B. only eight. 



In order to assist young Entomologists easily to be able to name 

 their species, I arrange the genus in the following form ; but first 

 I should observe that many of the species have a trigonal mark 

 on the costa, extending nearly to the inner margin. 



Note. — The species marked § have not yet been detected in 

 this country. 



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