259 
of the scales in rings, each scale above or below the interval be- 
tween two scales of the preceding or the following row, so that 
regular, transverse, and oblique series are evident, if the arrange¬ 
ment has not become a little obscured by irregular contractions 
of some part or other of the peduncle. 
Also in its mouth feet (Fig. 20 c—d) Mitella mitella strikingly 
differs from the other species of the genus. The man dible has 
Fig. 20. Mitella mitella ; South of Vitalis Point, Mindanao. a adult specimen, b capi- 
tulum and fragment of peduncle of a quite small specimen ; c mandible, d maxilla. 
[a natural size, b X 22, c—d X 33]. 
four main teeth, the second being situated in the middle of the 
cutting edge; in the large excavation between the first and the 
second tooth, and a little beside the cutting edge, an accessory 
small tooth is developed. The lower edge of the mandible is armed 
with a tuft of rather long spines. — The maxilla has an extra- 
ordinarily stout and large upper spine; below this a pronounced 
excavation is found, and halfway down the cutting edge yet an- 
other, shallower excavation; the cutting edge is densely armed 
with strong spines, but has no special tufts of bristles, as other 
specimens of the genus. 
Caudal appendages are present; they have six segments 
and are richly armed with hairs in their outer parts. The penis 
is, on the other hånd, almost destitute of hairs. — 
Only one smaller specimen was observed of Mitella mitella (Fig. 
20 b); although the skeleton is fairly well developed we can see 
17* 
