2 G. C. Crick — On AcantJioteuthis speciosa. 



bearing two rows of hooks, are attached to an elongated irregularly- 

 shaped body; and at a later date, in his "^Gruudzuge der Palaeon- 

 tologie " (p. 443), Professor Zittel also refers to this species the 

 phragmocone and pro-ostracum which he had previously (" Handb. 

 d. Palaeont.," pp, 510-1) assigned to a distinct genus (Ostracotenthis). 

 He states, moreover, that " in the Lithographic Stone of Eichstadt 

 a slab has been lately found which displays the shell and the im- 

 pression of the animal in association. In the body is an ink-bag ; the 

 bead is surrounded by ten arms, each furnished with two rows of 

 horny hooks." 



Since remains of the animal in association with the arms are 

 so seldom found, it seems desirable to place on record a speci- 

 men which has recently been acquired by the British Museum 

 from the Lithographic Stone of Eichstadt, Bavaria (Plate I). 



The specimen, which is exposed on the surface of a slab, has 

 a total length (including the arras) of about 380 mm. Tlie arms 

 are well shown ; the impression of the body is more obscure, 

 but can be fairly well made out in a very oblique light. Seven 

 or eight arms (a) can be counted, but they are so disposed upon each 

 other, and some of them so obscured by dendritic markings, that 

 their exact number cannot be ascertained. The longest is fully 

 120 mm. in length. The booklets (g) are arranged in two rows on 

 each arm ; they are small near the head, gradually increase in size 

 along two-thirds of the length of the arm, and become smaller 

 towards the extremity. The booklets themselves are not preserved, 

 only their impi-essions. The largest (h) is 7'5 mm. long, and the 

 length of its oblique base 2-75 mm. The impressions show that 

 the central portion of each booklet is depressed so as to leave a ridge 

 on either side, exactly as Miinster described in A. speciosa. At the 

 base of the arms there is a depression filled with calcite (b), indi- 

 cating the position of the head. Immediately behind the arms there 

 is an oval impression, the smaller end of which is directed back- 

 wards ; its outline is much more convex, and also more distinct, 

 on the right than on the left side of the specimen ; the greater part 

 of the right side of this impression is covered with a thin whitish 

 film, probably the remains of the mantle. Two subparallel obscure 

 grooves extend from the mass of calcite (&) across this impression, 

 and pass posteriorly into a triangular depression filled with calcite (c) ; 

 near its anterior end the gi-oove on the right gives off a branch 

 which curves backward and outward, and appears to meet a groove 

 which is continuous with the right side of the triangular depression. 

 From the posterior portion of the oval impression already described 

 the outline of the body gradually expands into a leaf-shaped form, 

 the greater part of which is also covered with a thin whitish film, 

 probably the remains of the mantle. This leaf-shaped portion 

 appears to be formed of two lappets (e and /), each of which termi- 

 nates posteriorly in a somewhat indistinct submucronate point, and 

 bears several very shallow grooves, some of which are parallel to 

 its margin. Posterior to the triangular mass of calcite (c), there is 

 a well-marked shallow depression with subparallel sides that is 



