Art. XIX.—On a Marine Galaxias from the Auckland Islands.
[Read before the Wellington Philosophical Society, 11th February, 1902.]
This fish was taken out of the mouth of a specimen of Merganser australis during the collecting excursion to the southern islands of New Zealand made in January, 1901, by His Excellency the Earl of Ranfurly. This expedition, which only lasted three weeks, collected twenty-two undescribed species of animals—viz., one bird, one fish, one slug, four beetles (including a new genus), fourteen flies, and one earthworm. In addition, much new information was obtained about the birds and about the development of some of the plants. This shows how much must yet remain to be done.
Galaxias bollansi, sp. nov.
Body elongated, the height being less than one-sixth of the length. Breadth of the head about equal to the height of the body. Length of the head one-fourth that of the body. Diameter of the eye about one-fourth the length of the head, or two-thirds the length of the snout. Lower jaw a little shorter than the upper. Maxillary reaching to the posterior margin of the eye. Length of the pectoral fins two-thirds the distance to the base of the ventral fins. Ventral fins two-thirds of the distance to the anal. The anal fin, when laid back, does not extend to the commencement of the caudal. The least depth of the tail is less than the distance between the end of the dorsal and the end of the tail. Caudal fin rounded. Dark olive-brown, with irregular vertical bands of dark-brown on the tail. A large pale spot on the preoperculum. Fins dark, unspotted.
I have named this fish after Captain John Bollans, of the Government steamer “Hinemoa,” who is an acute observer, and takes a great interest in natural history.
The following are the dimensions of the specimen: Length (without caudal), 3.5 in. Depth of the body, 0.55 in. Least depth of the tail, 0.35 in. Length of the head, 0.88 in.; length of the snout, 0.25 in. Diameter of the eye, 0.18 in. Breadth of the head, 0.6 in. Length of pectoral fin, 0.6 in.; of ventral fin, 0.6 in. Distance from base of pectorals to ventrals, 0.9 in. Distance from base of ventrals to anal, 0.9 in. Distance from dorsal to end of tail, 0.55 in.
This species is most nearly related to G. fasciatus, but differs from that species in its more elongated form, the larger
maxillary, the short anal fin, and the distance between the dorsal and the caudal, as well as in its markings.
Its eye is, rather larger than usual, but I do not think that it is the young of G. fasciatus, on account of its large maxillary bone and the pale spot on the preoperculum, which is probably very constant in all ages of the fish. Also, G. fasciatus is not known to breed in the sea in New Zealand; the old ones are never caught going down to sea, nor the young ones going up the rivers. The only species of Galaxias in New Zealand which breeds in the sea is G. attenuatus, and the young, known as whitebait, ascend the rivers in spring in a much earlier stage of development than the present fish.