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Wm. E. Hoyle, 



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is the smallest, in one instance the first and third are subequal. The proximal and lateral small suckers 

 have the horny ring finely denticulate, the teeth larger on the distal than on the proximal side of the ring ; 

 the same is the case with the small suckers immediately succeeding the large ones, but those forming a 

 group at the tip of the tentacle have smooth rings. The horny ring of the large tentacular suckers is 

 smooth as is that of a few smaller ones in the interspaces between them. 



The Surface of the dorsal aspect of the head, body and arms, is covered with the close-set 

 flattened tubercles, varying from 1 to 2 mm in diameter ; they are largest in the centre of the back 

 (PI. Va, Fig. 8) and head (Fig. 7), becoming smaller and less closely packed towards the sides. With a 

 simple lens these tubercles are seen to be Compound, consisting of a central papilla with from four to 

 seven in a circle round it (Fig. 9). It is quite possible that in a state of erection these structures might 

 present the appearance shown by Quoy and Gaimard (op. cit., tab. 1, figs. 7, 8), though I hardly think it 

 likety they can attain so great a length as there shown. Their microscopic structure is described below. 

 The under surface is smooth except for two elliptical patches one on either side of the middle line of 

 the lower surface of the mantle (Fig. 4). These are very distinct in the largest specimen, less so in the 

 other two ; their colour (in the spirit specimen) is a pale dull yellowish, the pinkish tinge and the dark 



Fig. 9. 



Fig. 10. 



Fig. 9. Sepia tubereulata, buccal merabrane and inner and outer lips, showing spermatophores adhering to the latter. 



Natural size. - 



Fig. 10. Radula of Sepia tubereulata. X 2 °- 



brown chromatophores seen in the rest of the mantle being conspicuously absent. This portion of the 

 surface is thrown into much larger wrinkles than the rest, but whether these are entirely or only partially 

 due to the action of the alcohol, there are no means of deeiding. The minute structure is described below. 

 The Shell (Figs. 5, 6) is broadly elliptical in the anterior half, the lateral margins more 

 separated behind so as to produce a sub-angular contour. The chitinous margin is of medium 

 breadth from 3 to 4 mm. The dorsal surface has a slightly elevated, rounded ridge, along the median 

 line, becoming gradually broader as it passes forwards, it is closely covered with rows of tubercles arranged 

 parallel to the anterior margin ; in the posterior half these tubercles become fused into a fine irregulär 

 network. The ventral surface is smooth and elevated, the shell being thickest just in front of the middle; 

 the last loculus has an index of about 33, and is bounded behind by lines inclined to each other at an 

 angle a little less than a right angle, and connected by a broad blunt curve in front. The striated area 

 is much hollowed, and is marked by lines roughly parallel with the curve just mentioned, the angle becoming 

 more obtuse posteriorly ; the lines are finely undulate; it has a distinct groove along the middle line. The 

 inner cone consists of two broad flat chitinous Strips, bordering the posterior third of the striated area, 

 and uniting in the middle line behind to enclose a very shallow depression. The spine is short and blunt. 



