274 PEOCEEDINGS OF THE MALACOLOGICAL SOCIETY. 



long ; and the third the two inner ones {c, d), each about 40 ram. long. 

 The longest pair seems to have been comparatively slender ; whilst 

 the others are relatively broader and taper very quickly at their 

 distal ends, 



"With regard to the relative position of the arms, it is to be noted 

 that in the view of the fossil that is here presented the two longest 

 arms are the outer ones on each side («, / ) and occupy a lower level 

 than all the rest, whilst one or two of the booklets of each of the 

 medium-sized pair of arms (l, e) are on the top of those belonging to 

 the smallest pair, and the medium-sized arm on the right {e) certainly 

 seems to occupy a higher level than the smallest arm on the same 

 side {d). Although one of the booklets about 13 mm. from the 

 proximal end of the arm d appears to rest on a booklet belonging 

 to the medium-sized arm e, the base of the arm itself seems to be below 

 that of the medium-sized arm on the same side. On the left side some 

 of the booklets of the medium-sized arm {h) rest upon those of the 

 smallest arm (c) on that side, but the base of the longest arm is not 

 preserved ; in fact, this arm is indicated merely by the impressions of 

 a few of the booklets {a). If this interpretation of the position of the 

 arms is the correct one, in the view of the fossil that is here presented 

 the two medium-sized arms are uppermost ; tlie two longest, lateral ; 

 and the two smallest, the lowest. 



The ink-bag is shown. There are a few pieces of the pro-ostracum 

 upon it, whilst the slender longitudinal rib below the ink-bag may 

 possibly be the median rib of the pro ostracum. If so, the aspect of 

 the fossil that is presented is probably dorsal. Although, as seen 

 from Professor Buckman's figure, the head of the fossil when first 

 described was placed almost at right angles to the rest of the body, 

 the present writer has no reason to doubt that it belongs to the 

 rest of the fossil. If the present interpretation of the order and 

 relative position of the arms is correct, the medium-sized pair were 

 dorsal ; the longest, lateral ; and the shortest, ventral. 



Specimen No. 2 (PI. XXIII, Fig. 1). — This specimen from the Lias 

 of Lyme Regis [B.M. No. C. 3,007] shows the ink-bag and its duct 

 bearing upon their surface fragments of the nacreous pro-ostracum, 

 whilst at the lowest portion of the fossil a part of the phragmocone is 

 preserved. It would seem, therefore, that it is a dorsal aspect of the 

 animal that is here presented. There is an irregular depression in the 

 region of the mouth. The length of the specimen from the base of 

 the arms to the posterior end of the ink-bag, at the anterior end of the 

 phragmocone, is 125 mm. Six arms can be seen, but though differing 

 in length the pairs cannot be easily made out. All their proximal 

 ends are united. Commencing the description at the extreme left of 

 the specimen, the first arm (a) is 30 mm. long, but distally it ends 

 abruptly, being intercepted by the edge of the slab ; its proximal end 

 appears to pass beneath the second arm (b). The booklets are rather 

 large in proportion to the size of the arm, and are rather wide apart. 

 The second arm {h) is about 50 mm. long and appears to be complete,, 

 the distal end being quite acute. Its proximal end seems to pass 

 along the left side of the hollow at the base of the arms. The 



