ON THE SYNONYMY OF THE PERLITES. 33 



sion, I shall at present merely employ the name. Neither of 

 the species has ever been described under any other generic 

 appellation. 



Sp. 1. Eust. Thalia. Subnigra; alae opaeae, fuscae, macula subrotunda 

 pone medium albida ; pedes nigri, femora basi testacea, tibiae prope 

 basin testaceo annulatae. (Corp. long. .5 unc. ant. .5, set. caud. .05, 

 alar, dilat. 1 425 unc.) 



The apical portion of the forewings is completely reticulated, and the 

 costal cell interrupted by very numerous transverse nervures, the hind wings 

 possess similar characters ; the wings of the female are abbreviated occa- 

 sionally (but not invariably) in the same manner as those of the male in the 

 British species of the restricted genus Perla; the antenna have a large ba- 

 sal joint, and are somewhat longer than the body; the caudal setce are ex- 

 tremely short, scarcely equalling in length the diameter of the abdomen ; 

 they are curved, of uniform thickness, and are composed of few joints: in 

 colour this insect is nearly black, the forewings are opaque and dark brown, 

 with a nearly round white spot situated rather beyond the centre; the hind 

 wings are brown without the spot; a series of testaceous spots extends along 

 the costal margin of all the wings, and round the extreme tips ; the legs 

 are nearly black, the basal portion of the femora, and a ring round each of 

 the tibia being bright testaceous. 



Inhabits Van Dieman's Land. There are four of this spe- 

 cies in the cabinet of the Rev. F. W. Hope, to whom I am 

 indebted for the loan of specimens. The extreme difference 

 between this and the cognate species, as regards the caudal 

 setae, would have induced me to raise it to the rank of a ge- 

 nus, had not Mr. Westwood, on examination, considered it to 

 belong to his genus Eusthenia. 



Sp. 2. Eust. spectabilis. (Corp. long. 1 unc. alar, dilat. 2 unc.) 



„ „ Westwood; Translation of Cuvier's 'Regne 



Animal ' by Griffith and others. Part Insects, vol. ii. p. 348, tab. 

 lxxii. fig, 4. 



Body, including the antenna and caudal setce of a very dark brown, near- 

 ly black ; the upper wings are opaque and brown, with an elongate red spot 

 near the costal margin, and rather nearer the base than the apex of the 

 wing, beyond and below this is a large blotch of dirty white ; the hind wings 

 are red at the base and black externally. 



Inhabits Van Dieman's Land. In the cabinets of the En- 

 tomological Club (donor J. O. Westwood), Rev. F. W. Hope 

 and Mr. Westwood. The very ample and reticulated wings 

 of this beautiful insect, together with its straight caudal setce, 

 and general habit, lead us to the giants of this group compos- 

 ing the genus Pteronarci/s. It is on this account that I have 

 placed the described typical species subsequently to the new 

 and aberrant one. 



Vol. III.— No. 25. n. s. d 



