THE NAUTILUS. 29 
callus; columellar lip reflexed over one-third of the umbilicus; 
aperture oblique showing the bands within. 
Four specimens give the following measurements: 
Altitude. Greater diam. Lesser diam. 
1 type No. 35601 29.5 mm. 37.5 mm. 33. mm. 
2 25.3 36.5 32. 
3 24.0 35. 29.5 
4 29.3 37s oS 
Specimens of this new species were included in a large col- 
lection of Philippine shells given to the Museum of Comparative 
Zoology by W. Cameron Forbes, former governor of the Philip- 
pine Islands. They were collected by Mr. C. W. Weber at 
Bacuit, northern Palawan. I have named this shell for Gov- 
ernor Forbes as a slight acknowledgment of the great interest 
that he has taken, and the work that he has accomplished, in 
adding to our knowledge of the fauna of the Philippine Islands. 
The specimen selected as the type, and described, is the most 
typical of the species. The specimen designated as number 
two in the table of measurements, is exactly similar to number 
one in color, and in the arrangements of the bands, differing 
only in being more depressed. Number three is very similar to 
number two in size and shape, but differs from numbers one 
and two in color, the lower band in this form having spread 
over the entire base, the upper band extending to the suture, 
leaving only at the periphery a narrow band of the typical 
naples yellow. Number four is similar to the type in size and 
form, and to number three in color. The variation is therefore 
expressed along two independent lines; first, a tendency for the 
shell to become more or less depressed; and secondly, for the 
bands to become broader and darker. Intermediates between 
all forms are in the series before me. The tendency in each in- 
dividual specimen for the color to become darker as the shell 
increases in size, is constant in both the light and the dark 
forms. 
The differences between this species and the description of 
what appears to be the most closely related species, Camaena 
