As this species in a near ally to several of the Dominion shells, I will quote from my paper (l.c.): “Through the kindness of Dr. Ed. Lamy, Paris, I have been enabled to compare a median valve of the holotype of jucundus with the New Zealand Acanthochitons. The median valve of jucundus is decorated with extremely even-sized, circular, raised, convex granules, and the dorsal area shows in the non-eroded portion, at sides and towards the apex, deep longitudinal grooving. It differs from zealandicus, doubtlessensis, and thileninusi in having longitudinally grooved dorsal area; from brookesi and the three above named in the flatness of the shell and its smaller, circular granules, it is nearer to zealandicus s.s. in the shape of its granules, but in jucundus they are more circular; I do not consider it a Dominion shell, and probably the locality of New Caledonia, given for bellignyi is correct.” Now the rediscovery of thileniusi has made it desirable to review the above in face of the distinct grooving of the dorsal area of that species. I find that the grooving in this area in jucundus is coarser, and riblets do not show, the rugose and wavy sculpture of that species, the granules in jucundus, as before noted, are circular, about 75 to 87 mmm. in diameter, whereas in thileniusi they are fully one-third longer than wide and the granules near the dorsal area are twice as long as wide; in jucundus the granules are consistently circular and of small size throughout. The only qualification I have to make in the description quoted from my earlier paper, is that the convexity of the granules referred to is slight only and may not be a persistent feature. Type in Mus. d'Hist. Nat. Paris.

Acanthochiton tristis.

Acanthochites tristis Rochebrune (l.c.) 1881–1882, p. 194.

Acanthochites tristis as being conspecific with thileniusi Iredale, Proc. Mal. Soc. Lon. vol. 9, p. 155, 1910.

Acanthochiton tristis Ashby in “Acanthoid Chitons of N.Z.” (l.c.)

That Iredale's surmise that this species is conspecific with thileniusi is without any foundation, will be clear from the following notes which I quote from the earlier paper: “Again I am indebted to Dr. Ed. Lamy for the opportunity of comparing a median valve of Rochebrune's holotype, with the New Zealand species. This median valve is nearest to mariae and stewartiana, but the shell is more arched and the sculpture less elongate, but it is still more easily separated from any known Acanthochiton, by its distinctive dorsal area, which in tristis is narrow and quite smooth, except for broad, transverse growth ridges. This cannot be considered a New Zealand shell.” Type in Mus. d'Hist. Nat. Paris.

Spongiochiton productus.

Spongiochiton productus Carpenter, 1873. Dall Proc. U.S. Nat. Mus. 1882, pp. 272, 283, 286, 289, 290.

Spongiochiton productus Pilsbry, Man. Conch. vol. 14, pp. 26–7; vol. 15, p. 7.