32 
Scalpellum (Smilium) kampeni, Annandale. 
Rec. Ind. Museum, vol. IN, pp. 267—270, figs. 1—4. (1909). 
This species has recently been described from a small speci- 
men taken off the east coast of Sumatra by Dr. P. van Kampen 
and now in the Indian Museum. Dr. Mortensen's collection 
contains a fine series of examples from Koh Chuen, Koh Mesan 
and Koh Rin, and the vicinity of one or other of these islands 
(15—30 fms.). There is also a specimen in the collection of the 
Copenhagen Museum from Singapore. These specimens were attached 
to the spines of sea-urchins, to the stems of Hydroids, and to dead 
and living shells. 
Dr. Mortensen's series shows that the species is a variable 
one and grows to a larger size than that of the type, the capi- 
tulum of which measures 7 x 4 mm., while that of the largest 
specimen from the Gulf of Siam measures 12 x 7 mm. The main 
Points in which variation is displayed by the hermaphrodites are 
(1) the colour of the valves, which varies from a deep rose-pink 
to milky white, (2) the stoutness of the valves, which are some- 
times thick, and (3) the direction of tlie sub-carina and the carinal 
latera, which sometimes point directly backwards, sometimes are 
turned downwards at. the tip, and sometimes are turned upwards 
to such an extent that they hardly project at all. As, however, 
no one of these characters appears to be correlated with any other 
and intermediate forms: occur as regards all of them, as there 
appears to be no anatomical differenee between the individuals 
with the most different types of shell, and as the strueture and 
form of the males appear to be constant, it is impossible to 
distinguish more than one species. I think it best in such cases, 
in which no definite break in the series can be detected, not to 
use varietal names to distinguish the extreme forms. 
An examination of the mouth-parts in several: specimens shows 
that the inner angle of the mandible is distinctly bifid, so that, 
including the blunt innermost. projection and the subsidiary tooth 
between the first and the second, there are in all six teeth. This 
