segment is coalesced with the cephalothorax. Three free terga for 
the other abdominal segments are developed, decreasing in size 
backwards, the hindmost being quite narrow. Generally, quite fine 
transverse lines may be traced from the front margins of the terga 
running across towards the ventral side; sometimes also a similar 
line may be traced from the anterior segment, coalesced with the 
cephalothorax. 
Of the 3 pairs of abdominal (or thoracic) feet the two anterior 
possess two rami, the last pair only one ramus (Fig. 10). Each 
ramus is bisegmented. The distal segment carries 7 (that of the last 
pair only 6) setæ with extremely delicate plumules; the outermost 
Seta is shorter than the rest. The proximal segment carries one seta 
on its inner corner; this seta is long on the outer ramus, short 
on the inner. The basal segment of each foot has a seta at its 
Outer end, just outside the articulation for the outer ramus. On 
the ventral margin of the basal segment of the first pair, medially 
to the origin of the inner ramus, is found a quite short seta. As 
already stated, the first pair of feet originates from the cephalo- 
thorax, the second from the first free abdominal segment, the third 
from the second; while the third segment is without feet. Ventrally 
between the feet sterna are developed, with a strong transverse 
ridge joining the members of each pair. In front of the first pair 
is a Y-shaped thickening on the cephalothorax; and behind the 
last pair a thickened transverse line on the abdomen. 
The elongated genital segment is densely striated transversely 
(this structure disappears on treating with a solution of potash). 
The genital openings are provided with strong chitinous lips 
(Fig. 9, 0); between them a spot is always observed, possibly where 
the copulatory openings have once been (Fig. 9%). The last post- 
abdominal segment carries on each side of the anus a small wart, 
evidently the furcal appendage, but completely devoid of setæ 
(Fig. 9, 7). 
Young stages, still unpigmented and pale, do not project with 
more than ca. 0,8 to 2,5 mm. outside their host. Closer examin- 
