132 
Transactions of the Boyal Society of South Africa. 
Adult $ : In boiling KOH the ^ becomes light brown in colour, and 
the liquid after about five minutes' boiling is champagne-coloured. After 
fifteen minutes the liquid is clear with a distinct carmine tint, which 
is retained throughout the boiling. 
The antennae are long, and comparatively slender, reminding one of 
Ps. fragilis, but those of the latter are even longer, and more slender. 
The antennal segments of Ps. trichiliae vary within the following 
range :— (1) 51-61 ; (2) 68-74 ; (3) 85-91 ; (4) 44-51 ; (5) 54-61 ; (6) 41-44 ; 
(7) 41-47 ; (8) 108. 
In 18 specimens all antennae fall into this series except one, which 
was obviously abnormal. Its measurements were : — (1) 61 ; (2) 68 ; (3) 
85; (4) 47; (5) 61; (6) 34; (7) 58; (8) 78. 
The conical apex of the terminal segment is in all cases very distinct. 
Hairs on antennae numerous, usual. 
Legs : The measurements of the legs are also remarkably constant, 
showing only a shght range of variation. The approximate or average 
series may be stated : — 
I. 
120 
130 
320 
85 
248 
40 
120 
II. 
120 
136 
375 
85 
320 
40 
134 
III. 
125 
150 
405 
85 
355 
50 
150 
The digitules of the tarsi are slender hairs ; those of the claw terminate 
in large clubbed ends. 
The dermis is transparent, but has a few single scattered gland-pores 
which are small, and scattered hairs. Between the antennae, on the 
dorsum, some of these hairs attain a length of 136 fx. 
The eyes are small, conical, and appear to be exceptionally distant 
from, and posterior to, the insertion of the antennae. 
The setae of the anal lobes and of the anal ring are, unfortunately, 
always bent in mounted specimens, again resembling Ps. fragilis in this 
characteristic, thus rendering their measurements difficult. The approxi- 
mate lengths are : — 
Setae of anal lobes : 270 long. 
Setae of anal ring : 170 ^ long. 
^ : Of the usual type, grey, with head and body darker, finely 
powdered. Caudal filaments two, nearly as long as insect without 
antennae, comparatively thick, white. 
Length of head and body, 1*35 mm. ; breadth across thorax, 0*38 mm. ; 
length of antennae, 0-75 mm. ; length of wing, 1*3 mm. 
Antennae usual, of 10 segments, measuring : — (1) 51 ; (2) 71 ; (3) 120 ; 
(4) 88 ; (5) 74 ; (6) 71 ; (7) 71 ; (8) 68 ; (9) 68 ; (10) 81 ^. 
All segments with numerous hairs. 
