FISHERY BULLETIN: VOL. 80, NO. 4 



it is long. The funnel-mantle locking cartilage is 

 simple. The anterior end is slightly pointed and 

 narrower than the posterior end. The groove is 

 shallow and wider posteriorly. The funnel organ 

 has a papilla on the anterior end of the dorsal 

 component (inverted V-shape), is small, and has 

 wide ridges on the lateral limbs. The ventral 

 components are oval but have pointed anterior 

 ends. The funnel valve is broad and its rounded 

 anterior edge reaches the level of the funnel 

 opening. 



The head is almost square in cross section, 

 slightly rounded at the top, and narrower than 

 the mantle (HWI 23.8-26.-4-28.3). The ventral 

 excavation is moderately deep and well marked 

 by sharp lateral edges. The three nuchal folds on 

 each side of the head are very prominent. The 

 first nuchal fold bears a tonguelike olfactory 

 papilla at its posterior end. The second and third 

 folds are crescentic folds with broad anterior 

 ends and are united to each other posteriorly by a 

 narrow membrane. From the posterior end of 

 the third fold a narrow membranous ridge 

 extends toward the dorsal midline but does not 

 quite reach it. In large specimens the nuchal 

 crest connects the three folds to each other and to 

 the midline, so that three oval areas are formed 

 on each side of the head posteriorly. The eye 

 opening is wide and has a deep sinus. Both dorsal 

 and ventral ocular "windows" are easy to 

 recognize, particularly in specimens that have 

 been preserved longer. 



The buccal membrane has eight stout supports 

 with connectives attached to the arms in the 

 order DDVD. The lappets are pointed and the 

 inner surface of the buccal membrane is rugose 

 and lacks papillae. The membrane is darker 

 than the supports; small chromatophores are 

 present in both structures. 



The arms are moderate in length; the ventral 

 arms, which are longest, are shorter than the 

 mantle length (ALL I, 49.7-56.1-63.4; II, 50.0- 

 58.9-G5.2; III, 51.3-5SU-66.2; IV, 53.1-61.7-11.1). 

 Weak keels extend along the distal third of arm I, 

 along the distal half of arm II, and from the base 

 to the tip of arm III. In the largest specimen the 

 swimming keel of arm III is slightly wider than 

 the arm width. The tentacular sheath along arm 

 IV is narrow, about half of the arm width near 

 the base, and reaches the tips of the arms. The 

 protective membranes are developed on borders 

 of all arms, but are more strongly developed on 

 the ventral borders. This is particularly so on 

 arm III, although the ventral membrane is never 



wider than the height of the hooks. The 

 trabeculae and the membranes are very distinct 

 even at the tips of the arms. 



The right ventral arm of the male is hectocotyl- 

 ized (Fig. 6B). The ventral protective membrane 

 on this arm is enlarged into an undulating 

 lappet, which extends from near the 9th or 10th 

 pair of hooks to the arm tip, although it becomes 

 progressively reduced in width distally. The 

 membrane is deeply notched at about two-thirds 

 of its length so that two semilunar flaps of un- 

 equal lengths are formed. The dorsal protective 

 membrane is less developed than the ventral pro- 

 tective membrane even in the area opposite the 

 enlarged lappet. In addition, the males have 

 numerous conical tubercles distributed on the 

 oral surface, at the bases of all the arms, and on 

 the areas between the bases of the hooks. 



The arm hooks are large (Fig. 6E), arranged in 

 two alternate rows, and enclosed by sheaths. The 

 ventral arms of both sexes bear the most hooks. 

 None of the hooks are unusually enlarged or re- 

 duced in either sex. The distal part of each arm 

 has two rows of suckers. The proximal suckers in 

 this region have long stalks and the inner rings of 

 these suckers have seven or eight large blunt 

 teeth (middle two teeth broadest) distally and 

 smooth proximally (Fig. 6C). The outer ring has 

 long pegs. The most distal pairs of suckers (with 

 about three teeth) are much reduced in size, 

 carried on short stalks, and have small openings. 



The tentacles are generally about the length of 

 the mantle (TLI 79.5-iO(U-129.0). The stalk is 

 slender, only about one-third of the width of arm 

 III. The sides are compressed and the cross 

 section is almost triangular. The club is narrow 

 (Fig. 61). The carpus includes between four and 

 seven smooth-ringed suckers and corresponding 

 pads arranged in an elongated series which is 

 limited on both sides by a narrow ridge. The 

 manus includes a dorsal row of four to seven 

 sheathed hooks and a ventral row of five or six 

 slightly larger hooks. The hooks (Fig. 6F) have 

 narrow bases. The largest hooks are not bigger 

 than any of the largest arm hooks. Marginal 

 suckers are absent and any sucker present along 

 the rows of hooks in young specimens certainly 

 represents an undeveloped hook. The dactylus 

 has 8 to 11 suckers arranged in two rows. They 

 have long stalks and wide openings. The sucker 

 rings bear teeth; six or seven short teeth distally 

 and six or seven very blunt teeth proximally 

 (Fig. 6D). The outer ring has many short pegs. 

 The tip of the club is blunt with a short over- 



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