274 
with one foot in each of Pilsbry’s subgenera, thus clearly illus- 
trating their invalidity. 
The internal structure of the lower part of the scutum (Fig. 
31 e) affords good specific characters, in contradistinction to the 
preceding species. 
In addition to previous descriptions we may add that the penis 
is stout, and only about half as long as the cirrus VI, it is almost 
a 
d e 
Fig 31. Megalasma minus from Menado Bay (Celebes). a large specimen with a 
small specimen altached to its scutum, side view, b the same specimen, carinat 
aspect, c medium sized specimen in lateral aspect, d carina of the latter, obliquely 
viewed from inside, e interior side of the left scutum. [all figures X 4]. 
entirely destittite of hairs except at its distal end, where a strong 
tuft of fine hairs are present. 
As in the preceding species we also find in Megalasma minus 
a pair of filamentary appendages seated close together al¬ 
most in the dorsal sagittal line of the animal above the first pair 
of cirri; the appendages are half as long as cirrus I. 
Genus Oxynaspis Darwin. 
In his classic monograph Darwin (1852, p. 133) in mention- 
ing this genus says: „As far as the valves are concerned, it is 
more nearly related to Lepas than to Poecilasma; but taking the 
entire animal, its relation is much doser to the latter genus than 
to Lepas; it differs from both these genera in the manner of growth 
