1. “Notes on some Australian and Indo-Pacific Echinoderms,”
In this article there are references to two common species of New Zealand Ophiurids. The author points out that the differences between the genera Pectinura and Ophiopeza are so inconstant that the two must be regarded as congeneric. He writes: “I have before me two excellent specimens of Pectinura maculata, Verrill, in one of which the supplementary oral plates [on the presence or absence of which chiefly the two genera have been separated.—W.B.B.] are well developed, while in the other they are entirely wanting. The specimens of Ophiopeza cylindrica, Hutton, which are accessible are all Pectinura in this particular, for one has 1, one has 4, and one has 5 supplementary oral plates. Moreover, in several of the deep-sea species of Pectinura these plates are quite rudimentary.”
He has a few remarks to make on each of these species, which are here reproduced, with synonymy and references.
(P. 117.) “Pectinura cylindrica.
“Ophiura cylindrica, Hutton, 1872. Cat. N.Z Echin., p. 3.—Ophiopeza cylindrica, Farquhar, 1895. Trans. N.Z. Inst., xxvii, p. 193.
“New Zealand. Littoral.
“Of three specimens in the Mus. Comp. Zool. collection, one has 5 supplementary oral plates, one has 4, one has 1. According to Farquhar (l.c.), there are none. Except between the first and second under-arm plates on one arm of one specimen, there are no arm-pores in the M.C.Z. specimens.
(P. 118.) “Pectinura maculata.
“Ophiarachna maculata, Verrill, 1869. Proc. Boston Soc. Nat. Hist., xii, p. 388 (reprinted in Trans. N.Z. Inst., xii, 1880, p. 232).—Pectinura maculata, Verrill, 1869. Amer. Journ. Sci. (2), xiv, p. 431 (footnote).
“New Zealand. Littoral.
“Of three specimens in the Mus. Comp. Zool. collection, one (disc-diameter 41 mm.) has 5 small but distinct supplementary oral plates, a second (disc-diameter 30 mm.) shows 1 very narrow supplementary oral plate, but the lower surface of the disc is so badly damaged it is impossible to decide positively whether this was the only one present or not; the third (disc-diameter 17mm.) has not the slightest trace of such supplementary oral plates. Pores seem to be constantly present between the first and second under-arm plates, but in the smallest they can scarcely be seen on two of the arms.”
The accumulation of specimens of all kinds of native invertebrates at the Otago University Museum will afford the opportunity for similar observations on variation in our fauna, for, as I have noted in a report on the Echinoderms collected by the “Nora Niven,” there is considerable variation of the sort dealt with above. I hope that some day students will be able to avail themselves of my material.