ON MAC KAY I A DIMORPHA 255 



Abdomen. — The bands on segments 1,2, and 8 are wide, 

 but narrowed on segments 3-7. There are two median hairs 

 on segments 1-8. In colour these bands, which are entire, 

 are of a clear brown. The stigmata are large and prominent. 

 On each band behind and inside the stigma, segments 2-6 

 show one fine hair and two or three stouter hairs near or at 

 the angle. These hairs are longer on the hinder segments. 

 Segment 7 has one or two extra hairs on the edge of the 

 band and shows an almost complete transverse row save in 

 the middle. Segment 9 has on the upper surface two patches 

 of short hairs, five in each, symmetrically placed about the 

 middle line. There are one or two terminal hairs and some 

 at the sides. The lateral band of the segments is -\ shaped 

 and there is only a slightly entrant appendix. The genitalia 

 are figured. The development of the paramera is relatively 

 great transversely. The penis is stout, with blunt apex. On 

 the under surface the segmental bands are sharply limited and 

 do not join the lateral bands. Each transverse band bears 

 a row of about six hairs (3, 3). The genital mark results 

 from a broad median connection of bands on segments 6, 7, 

 8. The lateral bands here bear one to two long hairs not 

 visible from above. The colour of the abdomen is clear dark 

 brown, on which the stigmata stand out distinctly. The 

 lateral bands are much darker than the ground colour of the 

 segments, being almost black. 



Legs. — These arc short, moderately stout, and docophoroid. 



9 . Head. — The clypeal outline varies and may be even 

 distinctly concave, as in the example figured. In general 

 chsetotaxy the sexes are alike. They differ, however, in the 

 relation of the bands to one another. In the $ , as already 

 noted, the occipital band runs directly to the ocular spot, 

 becoming indistinct there. Before it reaches this point it 

 sends off an internal branch, which fades away in the direction 

 of the hindmost heavy spine described. There is a distinct 

 gap between the occipital band and its connections on the 

 one hand and the antennal band on the other. In the 

 female the occipital band does not join the ocular spot 

 directly. It runs evenly to the base of the antennal and 

 there fuses with [a) the ocular band (which is more than a 

 spot in this sex), and (/>) the heavy internal transverse ba 



