Mr, A. Adams on Japanese Mollusca. 363 
the longest, twice as long as they are wide. The last joints 
shghtly compressed, smooth; the last has a strong tooth 
besides the final hook. ‘The first joint of the arms, arising 
direct from the knob of the calix, bears a pinnula immediately 
and has a syzygium; the second is without a pinnula; the 
third bears one; and the fourth has a pinnula, and also a 
syzygium. ‘Then the pmnule succeed each other, alterna- 
ting regularly, and always one syzygium between 3-5 joints. 
The joints of the arms are nearly twice as long as they are 
high, and, especially in the centre, are strongly wedged 
sideways. The first two pinnule are small, the third and 
fourth the longest ; then follow shorter ones, which, towards 
the end of the arms, gradually become longer and thinner, 
whilst the first issue with rather a broad basis. Length of 
the arms 80 millims., of the cirrhi 9 millims., of the longest 
pinnule 8 millims; the diameter of the central knob is 2 
millims. 
Unfortunately the disk is missing in the single specimen. 
The pinnule are speckled over with light and dark yellowish 
brown; the back of the arms is marked by two winding lines. 
Pandanon, near Bohol (Philippines), at a depth of 30 
fathoms. 
XLIV.—On the Species of Cxcide, Corbulide, Volutide, 
Cancellariidee, and Patellidee found in Japan. By ARTHUR 
ADAMS, F'.L.8. &e. 
PURSUING my investigations into the molluscan fauna of the 
Japanese Islands, | have in this communication to identity, 
enumerate, and systematically arrange the species of some 
families of which our knowledge in respect to geographical 
distribution was formerly somewhat limited. With regard to 
those curious but minute creatures, the Caca, it appears strange 
that I should have met with no new species. As to such a 
littoral family as Patellide, it is not singular that all the spe- 
cies should have been previously known, as casual observers 
and sailors are pretty sure to collect them. ‘These shore- 
inhabiting species are subject to very great variation ; and the 
chief difficulty in dealing with them consists in disposing of 
the varieties into groups which are natural, so as to reduce the 
number of the so-called species. All the localities are given 
solely on my own authority. Numerous other families still 
remain to be worked out before we can arrive at even an.ap- 
proximate knowledge of the Mollusca of Japan. ‘The speci- 
mens forming the material from which this enumeration has 
