STATEMENT OF SOME OF THE CHARACTERS 

 USED IN THE TABLES. 



The Sabethini and Culicini may be separated at once by the presence of a 

 small group of setse on the posterior portion of the postnotum and of a pair of 

 very coarse bristles projecting forward between the eyes in the former, which 

 combination of characters is absent in the latter. Most Culicini may be recog- 

 nized by the longitudinal rows of coarse setse across the disk of the mesonotum, 

 but these fail in a few genera. In the Culicini, the postnotum is usually with- 

 out setse, but two exceptions occur. In Dinomimetes one or two coarse bristles 

 are present on the postnotum, but its position in the Culicini is at once apparent 

 by the coarse bristles on the disk of the mesonotum. Many specimens of 

 Htemagogus have from one to three minute hairs well back on the postnotum, 

 but the position in the Culicini is indicated by the absence of the two coarse 

 seta? of the vertex. The small setse on the postnotum are sometimes diflBcult 

 to see, so that a compound microscope is necessary for certainty, though in the 

 larger forms they are generally recognizable with a hand-lens. 



In the Sabethini we separate the genera by the character of the prothoracic 

 lobes, whether large and closely approximated dorsally or well separated; by 

 the proboscis, whether long and slender or short and swollen at the tip ; by the 

 eyes, whether large and closely touching on the vertex of the face or smaller and 

 separated by a narrow area of integument, and on the shape of this area, whether 

 wedge-shaped or parallel-sided; on the claws of the hind tarsi, which in one 

 genus have but a single claw, all others having two claws, though occasionally 

 one is reduced in size ; by the presence or absence of setae on the clypeus. 



In separating the species of Sabethini, we rely upon the coloring of the scales 

 on different parts. The coloration of the prothoracic lobes is an important 

 character, followed by the distribution of white scaling on the occiput. There is 

 generally a border of white scales behind the eyes, but these may be partly or 

 wholly replaced by dark scales, giving various specific modifications. Next in 

 importance comes the scaling of the wings, whether the scales (particularly on 

 the forks of the second vein) are narrow or broad. Finally, we have the mark- 

 ings on the legs, which are more diversified, but must be used with caution, as 

 they are frequently subject to sexual dimorphism. Care must therefore be used 

 with these characters to be sure of the sex of the specimen under observation, 

 which is not always obvious with the smaller sabethids, as they often have 

 practically identical antenna in the two sexes. The abdomen is generally colored 

 dark above, silvery below, the colors separated on the sides in a straight line; 

 but in some species this separation is in an irregular or undulating line, afford- 

 ing a useful character. A few of the species have curious, paddle-shaped masses 

 of vestiture on the legs, the distribution and coloration of which afford specific 

 separations. 



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