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Show 1878.] MR. R. COLLETT ON CERTAIN GOBIOID FISHES. 321 success. In the winter months the fjord is covered with ice ; and in the spring and summer I had no opportunity of tracing them. In August 1874 I certainly found a couple of breeding females, together with some others which had already spawned ; but none of these differed in any point from the typical L. stuwitzii; and in September again the young of the year solely were seen. Therefore I could add nothing of importance to m y previous researches published in the * Norges Fiske' in 1874. It was almost accidentally that, in June 1875, I found one of the spawning-places ; and during a couple of excursions I succeeded in collecting a considerable number of fully developed specimens of both sexes. It then became quite evident that L. stuwitzii was based on the female and the immature males of the same species, the mature males of which were L. albus. On several occasions examples of typical L. albus, which all, without exception, proved to be old males, were taken from the same shoal as L. stuwitzii, all of which were females ready for spawning. Another lot consisted of somewhat younger specimens in various stages of transformation between both forms, all full-grown, but with the eggs and milt not yet perfectly ripe. Von Diiben and Koren described their species from four specimens taken in winter (in the month of December), and consequently out of their spawning-season ; but Parnell, on the contrary, had for the description of his Gobius albus 50 specimens caught in June in Solway Frith, thus just during their breeding-time. From Parnell's description we may conclude that he had only mature males at his disposal; nor does Dr. Gunther, in compiling his catalogue (1861), seem to have had at his disposal any females,-as may be seen from the fact that both these authors speak only of individuals with long teeth. By the kindness of Dr. Gunther I have received three specimens of the Scottish form, collected by Parnell himself; and one of these, curiously enough, proves to be a female with the minute teeth and the sloping fins, in other words, a typical L. stuwitzii. Thus Parnell had overlooked female individuals, perhaps few in number, and had drawn his description solely from the males. Having endeavoured to identify the two species of Western Europe, it remains to discuss the third and fourth species of this genus, the L. pellucidus of Southern Europe. In 1824, according to Dr. Gunther, a description was given by Nardo of a Mediterranean form under the name of Gobius pellucidus. I have not had an opportunity of seeing the periodical in which Nardo gave his original description (Giorn. Fis. Chim. di Stor. Nat. d. Pavia); but from the title of the paper (•* Osservazioni ed aggiunte all' Adriatica Ittiologia") it seems that his specimens were taken in the Adriatic. The species since Nardo's time has often been mentioned by those naturalists who have treated upon the fauna of the Mediterranean, and, as it appears, under somewhat different names. In Hist. Nat. Eur. Merid. torn. iii. p. 287 (1826), Risso mentions a species under the name Aphia meridionalis, n. gen. et sp., PROC. ZOOL. SOC-18/8, No. XXI. 21 |
