RHYPHOLOPHUS. 139 



en. XVI. RHYPHOLOPHUS. 



Two subniarginal cells ; four posterior cells ; discal cell present or 

 absent. Wings pubescent on the whole surface (Tab. I, fig. 14, wing of R. 

 nubilus ; fig. 15, R. rubellus). The second longitudinal vein originates at 

 a more or less acute angle, before the middle of the anterior margin ; the 

 subcostal cross-vein is a considerable distance (two or three lengths of the 

 great cross-vein) anterior to the tip of the auxiliary vein. Antennas 16- 

 jointed. Tibiae without spurs at the tip ; ungues smooth on the under 

 side ; empodia distinct. 



This genus is closely allied to Erioptera and distinguished from 

 it by the wings, which are densely pubescent on the whole surface. 

 As in Erioptera, the intermediate pair of feet is usually the 

 shortest here ; however this character is less striking in R. nubi- 

 lus. The antennae of some species are longer than usual in the 

 male sex and the joints of the flagellum are elongated, strongly 

 pedicelled, and pubescent (the genus Ormosia Rondani is founded 

 upon this character). The structure of the forceps of the male 

 varies in different species, and the study of these variations would 

 probably afford an insight into the true affinities between the 

 species. I have not had the necessary opportunities for the study 

 of these parts on living specimens. The principal modification 

 in the venation of the wings in this genus consists in the presence 

 or absence of a discal cell; when it is absent, we generally find 

 that the anterior branch of the fourth vein is forked (as in Tab. 

 I, fig. 15) ; this constitutes the genus Dasyptera of Dr. Schiner ; 

 but this is not always the case; sometimes, as in R. holotrichus, 

 it is the posterior branch of the fourth vein which bears the 

 fork. The course of the seventh longitudinal vein is also variable ; 

 sometimes it is nearly straight (R. innocens) ; sometimes arcuated 

 at the basis in such a manner that its first half runs very near the 

 sixth longitudinal vein (R. nigripilus) ; sometimes arcuated in 

 the opposite direction, with the concavity towards the sixth vein ; 

 in this case the tip of the seventh vein is approximated to the 

 tip of the sixth, and the axillary cell is broader in the middle than 

 at the end. This is the case with R. holotrichus, and reminds 

 of a similar course of the seventh vein in Erioptera (subgenus 

 Erioptera). 



Dr. Schiner, in subdividing the genus Erioptera, adopted two 

 genera for the species the wings of which are hairy on the whole 

 surface : Rhypholophus, with a discal cell, and Dasyptera, with- 



