Art. VI.—Brief Description of a new Species of large Decapod (Architeuthis longimanus).
[Read before the Wellington Philosophical Society, 30th November, 1887.]
Plates VII., VIII., IX.
It may be remembered that in 1879 I brought under the notice of this Society all the particulars obtainable regarding four gigantic Calamaries, stranded on various parts of the New Zealand coast, together with a detailed account of a very large specimen which was cast ashore at Lyall Bay, Cook Strait, and which I was able to sketch and measure carefully. The beak and pen, or internal skeleton, of this specimen are preserved in the Museum. In June, 1880, rather more than two years after the first specimen was cast ashore at Lyall Bay, another, but of an entirely distinct species, was reported to be lying on the
beach at Island Bay. In the last volume of “Transactions” Mr. C. H. Robson mentions that yet another, differing in many points from both the Wellington specimens, was found amongst the rocks at Cape Campbell. And now we have another of these highly interesting, but very objectionable, visitors. Early last month Mr. Smith, a local fisherman, brought to the Museum the beak and buccal-mass of a cuttle which had that morning been found lying on the “Big Beach” (Lyall Bay), and he assured us that the creature measured sixty-two feet in total length. I that afternoon proceeded to the spot and made a careful examination, took notes, measurements, and also obtained a sketch, which, although the terribly heavy rain and driving southerly wind rendered it impossible to do justice to the subject, will, I trust, convey to you some idea of the general outline of this most recently-arrived Devil-fish.
Measurements showed that, although Mr. Smith was over the mark in giving the total length as 62 feet (probably, not having a measure with him, he only stepped the distance), those figures were not so very far out; for, although the body was in all ways smaller than any of the hitherto-described New Zealand species, the enormous development of the very slight tentacular arms brought the total length up to 55 feet 2 inches, or more than half as long again as the largest species yet recorded from these seas.
The length of the tentacular arms is not a very important character, as they are known to be capable of extension or retraction at the will of the animal, at least to a considerable extent.
The fact that these monsters are only stranded in the winter, and their comparative frequency during that season, appears to show that they venture nearer shore at that time of the year, probably in order to feed on the shore fishes, and being caught by a gale are stranded, when not dead, in such an exhausted condition as to be almost powerless. Indeed I am inclined to think, that were they thrown ashore in robust health, they could not reach the water. My reason for saying so, is that I have tried experiments with specimens of the smaller Cephalopods caught in fishermen's nets, and have invariably found that whilst the true octopus will fight fiercely, he will steadily make for his native element, and has little difficulty in travelling on land; whilst the squid or decapod, although occasionally showing fight on land, appears unable to drag its long body over the ground, and therefore, if the tide is receding, it is sure to die before the next rise.
This specimen was a female, and to this fact may be due some of the points in which it differs from previous occurrences; but yet they are so considerable that I have no doubt a new subgenus at least will have to be created for its reception. In the
meantime I place it under Architeuthis, with the full knowledge, however, that it cannot possibly remain there permanently, the shape of the arms and the fins alone being sufficient to put it out of association with that genus. As soon as opportunity offers, I hope to make a further study and fully determine its affinities.
Sessile arms unequal in size and length, increasing from the dorsal to the ventral. First pair (dorsal) shorter than the body, triangular in section, with a stout fleshy membrane on each of the inner angles, the inner one slightly longer than the outer; this membrane can be folded over the suckers. Second pair (sub-dorsal), longer and stouter than the last, but not equal to the length of the body; rectangular in section, the sides and angles being, however, somewhat rounded, with thick fleshy membrane on each of the inner angles; these membranes are of equal width and strength. A thick crest runs along the outer face of these arms; it rises nearer the upper than the lower angle, and occupies about three-fourths of the face; its depth is nearly the diameter of the arm. Third pair (sub-ventral) still larger in all respects, and rather longer than the body; oval in section, the inner or sucker-face being flattened, each angle furnished as in the preceding arms with a fleshy membrane, the outer being slightly more developed than the other. Fourth pair (ventral) very long and exceptionally stout, rather longer than the head and body together; trapezoidal in section; stout fleshy membranes on the inner angles, the outer one the longest. A very stout fleshy crest on the lower posterior angle, and a much longer but slighter on the upper posterior angle.
The arrangement of the suckers on the sessile arms is very remarkable. The first (dorsal) pair carried fifty-four suckers on each arm, disposed as usual in two alternating rows; but these suckers were all small. The second had only forty-seven suckers, but these were very much larger than those on the first pair. The third had eighty-six, about the same size or a little smaller than those on the last pair. The fourth carried one hundred and forty-four, all about the same size as those on the second pair. As in the case of all animals belonging to this section, each sucker was stalked, the stalk being inserted on the side; each sucker is strengthened by a bony ring having a number of sharp teeth on the exposed edge. These bony rings are quite white when first taken from a fresh specimen; but after being in spirit for some time they assume a yellowish horn colour. They are all oblique (see figures).
Tentacular arms are very long and slender, more than six times the length of the fourth (ventral) pair of sessile arms, or of the head and body together. The arm is nearly round, and
of equal diameter throughout. The clavate portion is triangular, with a membrane on the posterior angle. A large and irregular cluster of small suckers and tubercles at the base of the club; this cluster gradually thins out and extends up the arm, the distance between the individual suckers increasing till they are about twenty inches apart; they then occur at regular intervals, a pair, sucker and tubercle, all up the arms. The larger suckers on the club are arranged in two alternating rows, with smaller intermediate marginal ones on each side.
The head is long, and of equal circumference, save a little behind the centre of the eye, where the cephalic cartilage causes a distinct prominence. The eye is prominent, with a well developed lid and anterior sinus.
The body is somewhat contracted a short distance behind the anterior margin, then it increases in circumference to the centre, whence it tapers to the tail.
The fins (Plate VIII., fig. 1) are broad rhomboidal, the posterior extremity produced into a blunt, but well developed, “tail;” the anterior lateral margins somewhat concave, and produced beyond the insertion, but the produced portion rounded.
The jaws (Plate IX., fig. 1, 2), when in position, as shown in Plate IX., fig. 3, form a powerful beak, resembling that of some gigantic bird of prey, except that the order is reversed, and in this instance the upper jaw fits into the lower, not lower into upper as is the case with birds. The tips of the jaws are black, which gradually passes into dark brown, and this again into a much lighter shade till the margin is reached, where the brown has quite disappeared and a border of dirty white remains. The palatine lamina is dark brown, becoming lighter toward the margins, which are white. The rostrum is strong, convex, acute, and curved forward, the cutting edges being concave, not, or but very slightly, notched at the base. The anterior edges of the alæ are uneven, being toothed or chipped all along. The lower mandible is very stout, not so much curved, no notch near the tip, which is acute; cutting edge straight, with deep notches at the base; succeeding this notch, and just on the anterior edge of the alæ, is a broad prominent lobe or tooth, the edges sloping from this to a depression, whence they rise again before rounding off.
The teeth of the radula are in seven rows, with on each side a marginal row of thin unarmed plates. The teeth are a light horn colour, but become darker in spirit. Those of the median line have three fangs, all truncate (see Pl. IX., fig. 4), the centre one much the largest, the laterals are slightly turned outwards; those of the sub-median line have two fangs, the inner one being the largest and turned towards the median tooth, while the outer one is slightly inclined towards its sub-lateral
neighbour. The teeth of the sub-lateral line are acute, stout, and much curved towards the sub-median. The laterals are slighter than the last, acute, and also curved inwards.
|Total length (including tentacular arms)||684|
|Body, from tip of tail to anterior margin of mantle||71|
|" circumference, one foot from anterior margin||54|
|" " at centre||63|
|" " immediately in front of fin||45|
|Head, from anterior margin of mantle to root of arms||22|
|Eye socket, long||5 ½|
|" " deep||3 ½|
|Tentácular arm, length||591|
|" " circumference||3 ¾|
|Sessile arms, first||59|
|" " circumference||12|
|Length of upper mandible, tip to end of palatine lamina||4 4/20|
|Length, tip to end of frontal lamina||2 17/20|
|Cutting edge of rostrum||14/20|
|" " ala||11/20|
|Tip to lateral border of frontal lamina||1 7/20|
|Lower mandible, tip to border of mentum||1 15/20|
|" tip to lateral border of ala||1 17/20|
|" height of tooth||5/20|
|Architeuthis longimanus. Sketch showing side-view, 1/24-th natural size.|
|Fig. 1.||Posterior portion of body, showing shape of fins.|
|Fig. 2.||Sucker from third (sub-ventral) sessile arm. Natural size.|
|Fig. 3.||Section of same. Natural size.|
|Fig. 4.||Bony ring extracted from same; front view. Natural size.|
|Fig. 5.||The same; side view, showing obliquity. Natural size.|
|Fig. 6.||The same; lower margin, showing scarp to allow the passage of the stalk of sucker. Natural size.|
|Fig. 7.||Bony ring from sucker of clavate portion of tentacular arm.|
|Fig. 8.||Section of 1st (dorsal) sessile arm.|
|Fig. 9.||Section of 2nd (sub-dorsal) sessile arm.|
|Fig. 10.||Section of 3rd (sub-ventral) sessile arm.|
|Fig. 11.||Section of 4th (ventral) sessile arm.|
|Fig. 1.||Upper mandible, natural size: a, rostrum; b, notch; c, inner end of ala; d, frontal lamina; e, palatine lamina; ab, cutting edge of rostrum; bc, cutting edge of ala.|
|Fig. 2.||Lower mandible, natural size: a, rostrum; b, notch; ab, cutting edge of rostrum; c, inner end of ala; d, mentum, or chin; e, gular lamina.|
|Fig. 3.||Both jaws in position (closed) and surrounded by the inner buccal membrane. Natural size.|
|Fig. 4.||One line of teeth from the odontophore, enlarged: a, median; b, sub-median; c, sub-lateral; d, lateral.|