PACHYTHELIA VILLOSELLA. 397 



very full and ample ; it presents very distinctly the Oiketicid notch at 

 end of nervure 2 ; this also exists in A. opacella, but is so slight as to 

 require looking for. The branch nervure from lb to inner margin 

 does not always reach it, and la is indistinct except where it joins 16. 

 The notch of hindwing is faintly reproduced in forewing at end of 

 nervure 2. Both fore- and hindwings have hair-scales basally and at 

 inner margin, but the general covering of the wings consists of scales 

 rather than hair-scales. These, on the general wing-surface, are 

 narrow (yo'ts °f length), narrowing gradually to each end, and 

 rounded or pointed at free end (not square or notched) and have five or 

 six striae. In the fringes, however, the scales are twice as long and 

 four or five times as broad, with ends showing one or two notches and 

 25 or more strife, and various intermediate forms ; along the inner 

 margin of the forewing there are longer (and pointed) scales much like 

 tbose on the wing-area, but two or three times as long, some longer 

 with only two or three striae, passing into hair-scales and without 

 hiatus into hairs, though in places hairs and scales are mixed without 

 intermediate forms. These apparent hairs are, therefore, not really 

 hairs but hair-scales. The forewing has a definite spine-area (haft- 

 feld) at the base of inner margin, tbe spines are very minute. The 

 antennas have 31 or 32 joints — the 1st very large and urn-shaped, the 

 2nd large, thick, narrowing outwards, the 3rd very short, half 

 its length, the 4th-7th gradually lengthen up to the 8th which 

 with the the 9th is about equal in length to its width ; they then 

 commence to narrow, so that the 24th or 25th is about half the 

 width and twice the length of the 8th or 9th. The whole length is 

 about 5*3mm. The flagellar joints, 3-31, each carry two pectinations ; 

 in a mounted specimen, joint 3, short as it is, appears to be a fixed 

 joint and has four plumules, the basal inner one very slender and no 

 longer than the thickness of an antennal joint ; on 4 the length 

 is about -6mm., on 7 nearly the full length is reached, viz., 1 '2mm. 

 on inner row and l*5mm. on outer, thence they become shorter until they 

 are about -3mm. on the 27th joint and are reduced to nothing in the 

 last. The antennal joints are clothed dorsally with scales about half the 

 size of those on wings and slightly broader, they are scattered over the 

 surface, without being in definite rows, 20-30 in a joint about the 

 middle of the antenna. The thickness of the pectinations is fairly 

 uniform, about ^ of that of the antennal shaft at the middle of the 

 antenna; they arise, apparently from the middle of the joint, but really 

 from its base, their outer margin sweeping straight clown to the 

 proximal end of the joint, but tbey are so inclined forwards that their 

 other side is beyond the middle of the joint. The thickness of plumule 

 is about •04mm.- , 05mm., and the length of the sense-hairs is about 

 •11mm. --15mm., these are black in colour, whilst the solid portions 

 are very dark brown. They are disposed along the under forward 

 surface of the pectinations, in two or three not very defined rows, they 

 number perhaps 100 to 150 on a pectination. The outer surface of 

 the plumules is perfectly smooth, not only free from hairs or scales, 

 but of any trace of points whence they may have been accidentally 

 removed. (In C. unicolor this surface carries a few scales.) The 

 under surface of the antennal joints carries sense-hairs also. The 

 basal joints carry two rows of about ten hairs each near their basal 

 margin ; medially they form a patch on the basal half of the joint 



