( Ixx ) 

 SC (Miirnylo.s.'onn; Si's/'a ; etc.); SC and SC'' are on a .stalk, and separate at 

 about one-fonrtli tlie way from the cell to the apex of the wing {subcogfal for//). 

 The radial vein, H, has the three branches situated as follows : R^ at the nj)i)er 

 angle of the cell or from the stalk St'^-'', but never standing far from the angle 

 of the cell ; IJ- nearer W than R', but never at the lower angle of the cell, 

 sometimes central. Of the two liranches of the median vein, M, the proximal 

 one, M-, arises mostly before or in the middle of the cell, seldom beyond ; 

 and M' stands proximally of the lower angle of the cell, which it approaches 

 sometimes without reaching it. SM' is absent ; it will be found designated 

 as (SM') in the descriptions of this Revision. SM'' is supported basally by a 

 remnant of SM', the two forming a fork ; .SM'' is rather long, disappearing 

 generally in SM- at a point where the wing is about as broad as SM^ is long. 

 The fork is mostly distinct, but in Macroglossum and some allied genera SM^ is 

 so close to SM'- and is so weak that one can scarcely speak of a fork ; while 

 in other genera {Manimba, for instance) the fork is very obvious. The cross-vein 

 D^ between R' and R" is very oblique ; D^ is mostly somewhat curved ; D* is 

 a direct continuation of M. The costal vein of the hindwing ends costally of 

 that point of the wing which is farthest from the base ; it follows on the whole 

 the curve of the_ costal margin, and is accordingly bent backwards and again 

 forwards in Degmuptera with sinuate and lobed costal edge. The first branch 

 of the snbmedian vein is generally designated as the "bar," connecting SO 

 with C ; it is the • vein forming together with C the small snbbasal cell of 

 Butterflies. This bar or SC branches off in or before the middle of the cell ; 

 in the latter case it is mostly weak and long {Macroglossum, for instance). SC^ 

 and R' are generally on a short stalk, seldom on a long one, or come from a 

 point or are slightly separate. R- varies much in position ; it is more or less 

 central, standing sometimes nearer the upper angle of the cell, sometimes nearer 

 the lower one. R' comes from the lower angle of the cell, and is nearly stalked 

 with M', this vein arising in all genera, except Cephonodcs, from before the 

 angle. Its position is occasionally constant within a genus or a species, and 

 different from that which it occupies in the next. M" stands mostly beyond 

 the middle of the cell, approaching M' occasionally. The first submedian vein 

 is absent as on the forewing ; SM^ and SM^ are present. The cross-vein D^ 

 between R' and R- is transverse or oblique, straight or curved ; D' is mostly 

 obliqne, seldom transverse ; while D' appears as prolongation of M. When D^ 

 is transverse, the lower angle of the cell is W or obtuse {Amphion ; recta ; 

 Rhodoprasina ; Cypa ; Lijcosphingia : etc.). 



The frenulum and retinaculum are j)resent in all generalised forms. There 

 exist, however, quite a number of genera in which they are reduced, vestigial, 

 or absent. Such genera are found only among the Acherontiinae and Ambulicinae 

 (= Spliingidae asemanophorae), whicli therefore may be called frenulum losers. 

 The frenulum is especially often lost in slow-flying species, or such species 

 as have a tumbling flight like Butterflies, and not the darting flight of the 

 greater portion of the Spkingidae. The wings of the frenulum losers are generally 



