5 
The shape of the body is rather short and clumsy; it is of 
about equal width throughout its whole length, only gradually taper- 
ng near the extremities. The tail is conical and of medium length. 
In the preserved specimen the body is slightly 
curved and tail is bent inwards towards the 
ventral side of the abdomen. 
The cuticle is very finely striated, but it 
has not been possible to see whether rows of 
points are present or not. Fine and delicate 
hairs are spread, apparently irregularly, over 
the surface. Just below the cuticle is seen a 
layer of pigment consisting of minute deep- 
brown granules; this layer is not covering all 
the surface of the animal, but is interrupted 
here and there for a Space; in the tip of the 
tail it is entirely lacking. 
The head is truncate and, as far as I have 
been able to ascertain, the entrance to the buc- 
cal cavity is surrounded by eight low lips in 
the intervals of which is seen a fine hair of 
almost the same delicacy and length as those 
spread over the body-surface. The lateral organ is found in the front¬ 
end, just behind the lips. It is spiral-shaped and much like the 
lateral organs known in the genus Desmodora ; it is relatively small 
and consists of only one loop and a half; the spiral line of the 
outmost loop does not end freely but bends inwards to the fore- 
going loop, a feature known, besides in the species of Desmodora , 
in some Cyatholaimi too, viz. C. ocellatus de Man and C. microdon 
Ditl.; but the most characteristic properties of this organ in the 
species under consideration are the paucity of the loops and the 
smallness of the whole organ. 
The buccal cavity is of a rather peculiar shape. In its distal 
half it is cup-shaped, broad and rather shallow. Its proximal part 
is cylindrical and contains a short spear or arrow the stem of which 
is slightly curved. In the front end this spear is pointed and pro- 
vided with a sharp barb much like that of a fish-hook. To the 
proximal part of the arrow strong muscles are attached, pointing 
obliquely forwards and attached to the inside of the wall of the 
Fig. 3. Oistolaimus 
ferox, ^ . 
