I have been unable to obtain a male, or even any other specimen, for Captain Black has not met with this species again. Hence, it is impossible to use the hectocotylus on which Robson lays stress.

It is thus only provisionally that this animal can be attributed to the genus Paroctopus.

Paroctopus zealandicus n.sp. Plate 40.

External Features.

The colour, when alive, is reddish-brown, though at times it would change to a grey, as observed by Mr. Adams. After preservation in formaline, it is dark grey with an olivaceous tint, not only on the dorsal surface, but over the entire body, including the inner face of the web and arms—even the suckers, though these are of a slightly lighter tone. After eighteen months in formaline the colour has become a dark chocolate.

The dorsal surface is roughened by closely set small rounded papillae of uniform size and distribution.

The ocular cirrus is represented by a comparatively large rounded tubercle.

The shape of the body is comparatively slender, measuring 210 mm. from the hinder end, or apex, to the level of the eyes, and its width about half way along is 125 mm. In other words, the body is eight inches by five.

In shape and size it approaches that of an adolescent Macroctopus maorum, as shown in my article on that species. The interocular (or “supra-ocular”) width is 58 mm.

The arms are about two and a half times as long as the body, and, except that the dorsal pair are the shortest, do not differ much in length. The formula for these arms is 2.3.4.1., commencing with the lengest arm. The actual measurements are given below:

The suckers on the dorsal arms are, as usual, larger than those of the other arms. Those of about the fifteenth to nineteenth pairs attaining a diameter of 20 mm.; the corresponding figures for the dorso-lateral arms is 17, for the ventro-laterals 11 mm. and for the ventral arms 10 mm.

The web or umbrella is deepest between the dorsal and dorsolaterals, that is between the arms numbered 1 and 2, and shallowest between the pair of ventrals. It is continued along the arms as a low ridge for about half their length.

The mantle aperture is wide (or, to use Robson's scheme, is indicated by “C”), in that it extends from the level of one eye to the level of the other.

The funnel reaches forwards to the origin of the web. The “funnel organ” is ill-defined as a broad-limbed W, the limbs presenting transverse ridges.

The Mantle Chamber. Pl. 40, fig. 1.

The funnel lock consists of a relatively large, thick semi-circular flap on each side, separated by a wide gap.

The “Adsiphonal pouch” (which Naef calls “Trichtertaschen” and Isgrove the “lateral chambers” of the funnel) is large, being

27 mm. in height, and its opening into the mantle chamber is 35 mm. wide, lying, as usual, just outside the flap of the funnel lock.

The Septum, which divides the chamber into a right and left cavity, and which may be termed the “intercameral septum,” is unusually short, being only 30 mm. in length in front of the “intercameral aperture.” This consequently is of great length, extending almost to the hinder end of the animal, though naturally it loses in height as it passes backwards. The free edge of the septum is a distinct muscular slip arching over the aperture and gradually decreasing in thickness as the height of the septum diminishes.

The gill is large and rather broad; with 9 lamellae on each side of its axis.

The ovipore is far forward and occupies what seems to be an unusual position, being placed on the face of the septum, just in front of the aperture and not, as commonly is the case, on the body wall. The ovipore is situated at the end of a flask-shaped vagina, which is coloured grey. The long axis of the flask is very obliquely placed, its base directed dorsally at an angle of about 45 degrees to the direction of the septum.

The Female Organs.

The ovarian sac is enormously distended by the multitude of contained ova, so that it extends forwards, concealing most of the renal sac, and reaches to the base of the gill. The eggs are mostly free in this sac, but a number are still attached to the anterior and dorsal wall, each egg being attached thereto by its long stalk, independently of the others. PI. 40, fig. 3.

The proximal region of the oviduct—that is, the “ovarian duct”—is quite normal, being broad, with a thin wall starting from the hinder limit of the sac and at the anterior limit dividing as usual into right and left tube leading to the oviducal (“sperm-oviducal”) gland. This is circular, bi-convex and deeply pigmented. The ovarian duct opens into it at the centre of its posterior face. The distal oviduct leaves the gland from the centre of the anterior face. Its wall is thick, its diameter narrow and its course slightly undulating as it passes over the renal sac outwards and forwards to reach the flask-shaped “vagina,” which has a thick muscular wall.

The Egg. PI. 40, fig. 4.

As I have mentioned the eggs are deposited singly or in small groups, attached to the sides of the aquarium tank each by its long stalk, which ends in a small granulated plate of irregular size and shape. The egg is a long ovoid, rather tapering distally, and measures some 5 mm. in length, enclosed in a tough capsule, which is produced into the stalk, which is 6–7 mm. long.

Though this animal presents the isolated eggs referred to by Naef as generic, yet the egg itself is much smaller than those of the species described by Robson, some of which attain a length of 10 mm., though that of the type species, P. digueti, varies apparently from 5–9 mm.

The Radula (Fig. 2).

The median or “rhachidian” tooth bears a single lateral cusp or “ectocone,” which varies in its position slightly in following

Discussion.

I have compared the details of the present species with the account given by Robson for five species which he includes in the genus. The present differs from each of them in sundry points. The form of the body is described as “squat,” whereas this term does not apply to the New Zealand species; nor does the colour, which is either “yellowish” or brown, or purplish (presumably after preservation), whereas the present animal is dark grey-olivaceous.

But shape and colour are variable in individuals of the same species, as has been noted for several; for instance, in his table of Indices Robson states that the width of the body of P. digueti varies between “52–100%” of the body length—that is, it may be nearly globular; again, for Octopus macropus he gives for the same item the figures “32–96%.” At any rate the present octopod exhibits a number of departures from the Indices for these four species of Paroctopus, so that it seems necessary to make a new species; though whether it should be referred to the genus Paroctopus, owing to the isolation of the eggs, whether this feature is sufficiently distinctive I am not in a position to determine, for the literature available to me is inadequate.

In addition to comparing the details with the four species of Paroctopus I have compared it with the accounts given by Robson for members of the genus Octopus, etc., and it fails to agree with any of them.

Bibliography.

Isgrove, Anne, 1909. “Eledone”—Liverpool Marine Biology Com. Monograph XIII.

Naef, A., 1923. “Die Cephalopoden.” Monograph 35. Fauan und Flora Golf di Napoli.

Robson, C., 1929. “Monograph of Recent Cephalopods,” vol. i. British Museum.

Octopus adamsi n.sp.

Two individuals from Port Chalmers, details of whose capture are unknown; they had been in the Museum collection for years before my arrival. Both are females and are well preserved in alcohol one of them (no. 29) has been on exhibition in the Museum and its body is very stiff and the arms displayed.

The shape of both is oval, pointed bluntly at the hinder end. The colour slaty, that is, a bluish—or purplish—grey, with pale buff undersurface.

The sculpture of the dorsum consists of closely-set, low, rounded papillae, which are so low as to give the surface an almost smooth aspect; but amongst them are a few which are produced into filaments. The low papillae are continued on to the base of the arms and web.

The length of the body is 45 mm. and 47 mm. respectively.

The arms in No. 28 are recurved, well stretched in a flat spiral, are approximately of equal length except that the dorsal is shortest: in the other specimen it was found, owing to their position in the museum jar, difficult to measure accurately.

The web or umbrella is not continued along the arms and the sectors are subequal.

The eyes are prominent; the supra-ocular cirrus is a low cone with roughened tip.

The mantle aperture is wide.

The funnel reaches about half way along the web, the funnel lock consists of rather large lateral ridges united across the mid-line by a low strip. The funnel organ is ill-defined.

The inter-cameral septum at a first glance appeared to be perforated by a very small interpallial communication, but further study showed that it was partly concealed by the adhesion of the membrane covering the viscera; it is in reality of normal dimensions.

The gill is composed of 8 lamellae.

The ovipore is situated on a smooth, low papilla in front of the base of the gill, and lateral of the renal aperture.

The female apparatus presents what seems to be rather unusual features. The proximal oviduct, or as I have called it in previous communications, the “ovarian duct,” is a slender tube which opens into the small oviducal gland at its forward pole, while from its hinder pole there issues the distal oviduct. Thus is a very stout, long U-shaped sac the distal limb of which passes forwards to enter the small vagina (Text fig.).

The female apparatus of Octopus adamsi. (X 2.)