292 
Proceedings of the Eoyal Society 
The Arms are subequal, the order of length being 4, 1, 2, 3, and 
nearly half as long as the body ; they are all more or less compressed, 
especially the ventral ones ; they have a distinct web along the 
outer margin, and a rather broad membrane runs up either side of 
the sucker-bearing face. The suckers are in four series throughout, 
not very obliquely set; they are large and spheroidal, and have 
meridional markings on the outer surface; the horny ring is smooth 
and surrounded by a narrow papillate area. In the hectocotylized 
arm of the male the first four rows of suckers are normal, then come 
two rows of gradually diminishing suckers, succeeded by four rows 
of minute ones, after which they again regain their normal 
dimensions. The umbrella is narrow, widest between the second 
and third arms, where it reaches up to the fifth row of suckers 
The buccal membrane has the usual seven points in the male ; in the 
female the two ventral are rounded off ; the spermatic cushion is 
exceedingly well developed, and has four deep transverse grooves. 
The outer lip is thin and longitudinally corrugated ; the inner is 
thick and bears numerous very long papillae. 
The Tentacles are absent. 
The Surface is smooth throughout. 
The Colour is dull grey, mottled with black above, yellowish below. 
The Shell is elliptical in outline } somewhat broader behind 
(especially in the female) ; the chitinous margin is narrow and does 
not form a complete ridge across the shell below the spine ; it forms 
two slightly expanded wings behind, and extends but a little 
distance over the dorsal surface , which is marked with coarse 
rugosities disposed in curved lines parallel to the anterior margin ; 
a distinct but low rib runs down the centre. The ventral surface is 
elevated on either side of a deep median groove ; the last loculus 
covers about one-fifth of the surface, and is bounded posteriorly by 
two slightly wavy lines, meeting at an acute angle ; the striated area 
is long, and the angle between the striae widens posteriorly. The 
inner cone is very well developed ; the limbs arise one-fifth the 
length of the shell forward, and gradually become more elevated 
until they enclose a deep conical cavity. The spine is strong, 
pointed, and somewhat curved laterally in the female example. 
Hob. Japan; purchased in the market at Yokohama. Two 
specimens, 1^,1? 
