Art. XXV. — On the Occurrence of Pedicellina in New Zealand.
[Read before the Otago Institute, 13th July, 1897.]
Among hydroids I found, growing on the stems of Obelia nigrocaulus, the only representative of the Polyzoa endoprocta yet recorded from New Zealand. It is Pedicellina gracilis, Sars, Plate XXII., figs. 1, 1a, 1b; Johnstone, Brit. Zoo., 385; Goodsir, Ann. Nat. Hist., xv., 380; Hincks, Ann. Nat. Hist. (2), viii., 360, and Brit. Zooph., 570.
This Endoproctan is quite microscopic, and may be recognised by the enlarged base of the peduncle, in which the muscular power is placed, and to which the remarkably energetic movements of Pedicellina gracilis are due, the part above being a rigid rod supporting the almost globular body. The variety mentioned by Hincks with the muscular swelling elongated and divided into two or three parts was also present.
The finding of this specimen has extended the geographical distribution of the Endoprocta in a rather remarkable manner. Formerly members of this order had been found only in Norway, Spitzbergen, White Sea, and Roscoff. Now it is found in New Zealand, quite the antipodes of all the localities in which it was formerly found. The fact, too, of this being precisely the same species, and even presenting the two same varieties, is noteworthy.
Explanation of Plate XXII.
Pedicellina gracilis, closed.
" with tentacles expanded.
A variety of the same.