146 
M. SASAlvI. 
arm and highest towards a point one-third from the base of the arm. Tlie 
ventral protective membranes are very broad, beint;- about thrice as wide as 
the length of the suckers, while the dorsal membranes are narrower than the 
length of the suckers. 
The fourth pair is nearly quadrangular, with a narrow web along the 
ventral outer edge, and a broad one along the dorsal, the proximal part of the 
dorsal web being as broad as the thickness of the arm ; the protective mem- 
branes of both sides are alike about half as broad as the length of the suckers. 
The arm-suckers are semicircular, with a broad aperture and oblique 
stalk, and they are arranged in two series ; the horny rings have sometimes 
blunt, sometimes sharp, teeth on the distal margin, surrounded by a papillary 
area with numerous striations radially arranged. The horny ring of one of 
the suckers in the fourth row from the base on the second arm of a male 
whose mantle-length is i 16 mm, has a large, thick, triangular tooth with 
acute point at the most distal edge, and on each side of it, seven flattened teeth 
somewhat thickly arranged and of much smaller size, some of these being 
blunt and some sharp ; the horny ring of a sucker from the sixth row shows 
characters nearly equal to the preceding ring, but all the teeth of this ring 
have much blunter cusps, and the marginal tooth on each side is very muc 
thicker, being as large as the median one (PI. IV, fig. 9a) ; the horny ring of 
a sucker from the tenth row has, on the distal margin, nine teeth which are 
much narrower and sharper than those of the preceding rows (PI. IV, fig. 9b). 
The size of the suckers varies a little in the different arms of each in- 
dividual, as the following table shows : 
Mantle-length 
Diameter of largest sucker of first arm.... 
,, ,, ,, ,, ,, second arm 
„ „ „ „ third arm . . 
„ „ „ „ „ fourth arm , 
mm. mm. mm. mm. mm. 
154 166 120 122 151 
. 2. 1 2.5 1.3 2 2.5 
• 3-4 3-8 2 2.5 3.5 
. 2.5 2.8 1.7 2.2 2.8 
1.8 
1 .2 
1-5 
