Zoobgy.} NATURAL HISTORY OF VICTORIA. \_MoUusca. 



of tentacular arms), one on each side of base of ventral arms; lips witli numerous 

 small wattles ; beak sharp, black. Colour: Dark-purple on back and upper surface 

 of bead, paler at sides and base of fins, the narrow outer edg-es of which are 

 darker; lower or ventral side paler; tentacular arms and inner face of sessile 

 arms whitish. Measurements: Length from anterior dorsal edge of mantle to 

 interval between fins behind, 8 inches; from ventral edge of ditto, 6 in. 7 lines; 

 width of fins at middle, about 1 in. ; width of body without fins, about middle, 

 4i in.; length of tentacular arms, 11 in. 6 lines; length of suckered club, 1 in. 

 9 lines ; width of club, including- 3 lines of'inner fin, 1 in. ; leng-th of inner fin, 

 9 in. 9 lines ; longest (ventral fourth) sessile arm, 6 in. 9 lines ; next (third) 

 pair, 5 in. 6 to 8 (on two sides) lines ; next (second) pair, 5 in. 8 lines ; dorsal 

 (first) pair, 5 in. 8 lines; depth of fin between dorsal pair; 1 in. 8 lines; next 

 pair, 1 in. 6 lines; next pair, 2 in.; next pair, 2 in. 7 lines; ventral pair, 

 2 lines. Width of head, 3 in. 6 lines; longitudinal diameter of eye, 2 in. 

 Taking- length of dorsal surface of mantle as 100 : the proportional leng-th 

 from ventral edge is i^-g-; width of fins at middle, -x^^; greatest width of body 

 without fin, yVo ; length of suckered club of tentacular arms, -i%-^ ; width of club, 

 including outer fin, tVo J longest sessile (fourth ventral) arm, y^; next (third) 

 pair, -pfnr; next (second) pair, -1^^ ; dorsal, ^-^. Another specimen gives length 

 of ventral arms to dorsal length of mantle as -f-^-^ (suckered portion, fW) ; next 

 pair, -f'^f-jj. Internal Shell: Elongate-ovate, semioval anteriorly, narrower pos- 

 teriorly, with slight concavity of sides about one-third from posterior end; anterior 

 two-thirds of midline of back nearly straight, posterior third with a gentle parabolic 

 curve downwards to edge ; spine thick, very short, curved downwards or towards 

 ventral edge, not reaching beyond margin of shell ; below spine a triangular space, 

 twice as wide as deep, filled with irregular, lacunose, spiny ])rojections of lamellae, 

 edg-es radiating from under base of spine ; a middle space of upper surface rather 

 more than one-third the width in front, rather less than one-eighth the width at 

 one-fourth the leng-th from posterior edge, convex ; separated from lateral, slightly 

 convex-shaped sides by two shallow, diverging impressions, disappearing- at posterior 

 fourth of length ; middle of posterior fourth of leng-th covered with coarse, irregular, 

 short, vermicular, tubercular ridges, the sides with strise arching forwards and 

 outwards. Margins brown and horny at edge, calcareous further in, narrow in 

 front and at .sides of anterior half, becoming wider and forming- steep sides 

 posteriorly, united behind ; a thick pad at posterior edge of hollow on ventral 

 surface, the portion of which marked with transverse undulating lines of cellular 

 growth is abo\it four-sixths of total marginal length, flattened behind, slightly 

 concave in middle, and convex at sides on front half; anterior two-sixths showing- 

 greatest convexity or depth of the shell at its posterior edge. Leng-th from anterior 

 to posterior edge, 5 in. 10 lines; greatest width (a little in front of middle), 2 in. 

 5 lines, or fniT; gi'eatest depth, 7 lines, or -r"^; length of spine, 1^ lines, or tou ; 

 adult shell about 11 in. long, rather wider behind the lateral concavities, and 

 without spine, which is often absent in much smaller specimens (probably old 

 dwarfs). Sixteen sutural spaces in 6 lines near middle of underside of shell. 



Reference.— Cat. Mol. B.M., Ceph. Ant. p. 103. 



This is the largest and commouest s^iecies of Sepia on our 

 coasts, and its internal dorsal shell or " Cuttle-fish Boiie " is 

 abundant on the shores everywhere in the Colony, although it has 

 not been figured before. I think the character of the relative 

 order of successive length of the sessile anus is not so satisfactory 



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