The egg of this species has been described and discussed by Professors McIntosh and Prince, by Mr. E. W. L. Holt, and by myself. Raffaele, in his paper in the Mittheilungen of the Naples Station, vol. viii, described the yolk in the ovum of Callionymus festivus as having a peripheral layer of yolk-segments, but no reticulated marking on the surface of the vitelline membrane; while all we English observers have agreed in stating that the egg of Callionymus lyra, our common dragonet, has a reticulated marking on the vitelline membrane, but no yolk-segments. I was, therefore, very much surprised, in examining some eggs of this species from the tow-net this year, to find that there actually was a peripheral layer of yolk-segments, which had hitherto been overlooked.

It may be well to preface the paper on the Production of Artificial Baits by a short statement as to the way in which the experiments were taken up by Mr. Hughes.

Dr. Wemyss Fulton has made an extensive investigation of the distribution of immature sea fishes, and has published his results in the Report of the Scottish Fishery Board for the year 1889. He had at his disposal a sea–going vessel specially adapted to fishery investigations, and his data were obtained exclusively by means of this vessel. As scientific Secretary to the Board Dr. Fulton is attached to the Office in Edinburgh, and the observations he required were made and recorded according to his directions by the naturalists on the Board's steamer “Garland.” The conception and the execution of this investigation are both admirable, and it has supplied a great deal of definite knowledge upon subjects of great importance on which previously we knew little or nothing. The enquiry consisted in determining firstly, from the examination of a large number of specimens, the minimum and maximum size of sexually ripe specimens smaller than this minimum size at various depths and various distance from shore. The enquiries described in the present paper are to some extent similar to Dr. Fulton's, but in the main they are different both in object and in method. My first object was as far as possible to ascertain something of the rate of growth of sea–fishes of various species. With this purpose, I have searched for young specimens in all possible ways, and have measured and preserved all I could meet with.

Although the Isle of Wight has been a favourite haunt of the geologist and the palæontologist, references to its present marine fauna are exceedingly rare in zoological literature. Early in May of the present year, however, I had an opportunity, at the suggestion and through the kind hospitality of my friend Mr. Poulton, of examining the littoral fauna of the eastern shores of the island, and of making a considerable collection of zoological specimens. A list of the species which I obtained will be published as soon as I have had time to complete the examination of them; but several of the Ascidians throw so much light upon the brief and obscure descriptions of certain species, that I believe it will be serviceable to give a full account of them without further delay, especially since the pressure of other work may prevent an early appearance of the complete list.

1. Historical Review.

The history of our knowledge of this subject is complicated and curious, and is not quite correctly narrated in any English publication, not even by Balfour in his account of the development of Crustacea (Comparative Embryology, vol. i). The story begins with the establishment and definition of the genus Phyllosoma by Leach in 1818. Various succeeding zoologists included descriptions of species of Phyllosoma in their works, but the result of all previous investigations are included by Milne Edwards in the comprehensive account of the genus given in his Hist. Nat. des Crustacés, vol. ii, 1837. The state of knowledge at that time may be briefly summarised as follows:—The Crustaceans known by the name Phyllosoma had been found near the surface of the ocean in various parts of the world. They varied in size from less than half an inch to two inches. They were, when alive, of glassy transparency; the body was remarkably flat, and expanded horizontally, while the limbs were long, slender, and biramous. The body consisted of three parts; firstly, a head having the form of an oval leaf, bearing at its anterior extremity a pair of eyes on long stalks and two pairs of simple antennæ. The mouth was situated beneath the middle or posterior third of the head, and surrounded by an upper and lower lip, a pair of maxillæ, and the first pair of maxillæ. The second pair of maxillæ and the first pair of maxillipeds were rudimentary and situated behind the mouth. The second part of the body was the thorax, quite as flat but not so large as the head; it was usually broader than long.

In my paper on the Reproduction of Fishes occurring at Plymouth, published in this Journal, vol. i, p. 10, 1889, I identified as the egg of the pilchard, a pelagic egg commonly found in the tow-net in summer, and distinguished by three obvious characters, namely: (1) an unusually large perivitelline space; (2) a single large oil-globule in the vitellus; (3) a completely subdivided yolk. I also stated that ripe spawning pilchards occurred off Plymouth between June and October, but always at some distance from land, being usually taken in mackerel nets worked to the south of the Eddystone. My identification of the egg, taken in the sea, was founded upon a comparison between it and the eggs pressed from the ripe but dead female pilchards obtained from mackerel fishermen. The latter eggs were already dead, and did not float, but sank in sea water, but they possessed a single oil-globule, and the yolk in them consisted of a number of yolk-spheres. The large perivitelline space was absent, because it is only formed when living eggs are extruded into sea water.

Raffaele had previously described two kinds of pelagic eggs found at Naples, which he recognised, from their divided yolk and the characters of the larvæ hatched from them, as belonging to some species of Clupeoid. The larger of these eggs he attributed to Clupea pilchardus, but did not give his reasons. This egg is in all respects similar to that identified as belonging to the pilchard by myself at Plymouth. It is well known that the sardine of the French coast and of the Mediterranean is the same species of fish as the pilchard of Devon and Cornwall.

When trawling with a small beam trawl on July 9th last, a couple of miles north of the Eddystone, I obtained a large number of specimens of a fish which was quite unfamiliar to me. I found it was Crystallagobius Nilssonii. The chief characters distinguishing the species are the presence of only two rays in the anterior dorsal fin of the male, and the almost complete absence of this fin and of the pelvic fins in the female. The adult male is 4.4 cm. long, the female about 3 cm. When alive the fish is very translucent, and it is entirely destitute of scales. The species was first described by Düben and Koren in 1844 from half a dozen specimens taken near Bergen. Robert Collett has well described it in the Proceedings of the Zoological Society for 1878, having taken twenty-eight specimens at about 30 fathoms in the Christiania Fjord in the years 1875—1877. Only forty-five specimens altogether had been taken off the south and west coast of Norway at the time when Collett wrote. I captured 201 specimens in a single haul of the trawl, 188 of which were female and 13 male. Nearly all were adult, the eggs being visible through the integuments in the female. A few not quite full grown are included among the 188 reckoned as female, and some of these may prove on closer examination to be young males. In any case the excess of females is very great.

It may be taken for granted that, apart from its purely scientific value, a knowledge of the physical conditions affecting the waters of the sea has been shown to throw considerable light on many important economical questions. In its bearing on fish and fisheries, the inquiry may be said to have reached a point where it is conclusively shown that there is a problem to solve.

In a report of the Herring Committee of the Scottish Meteoro logical Society we find the following stated as preliminary results:— “If, during the herring season, there be a district where, from any cause, the temperature of the sea is lower than in surrounding districts, the catch of herrings is heavier in that district; and conversely if there be a district where, from any cause, the temperature of the sea is higher than in surrounding districts, in that district the catch of herrings is less. Among the causes which bring about a local increase or decrease of sea temperature, the chief are clouded or clear skies in respective districts, according as these occur during the day or during the night.

“The above refers to local fluctuations of temperature during the fishing season, when the temperature of the sea is high. It appears from the observations of past years that the herring seasons have closed about the time when the temperature of the sea in its annual fall has fallen generally to 54.5° F. It is of importance to ascertain how far this relation exists from year to year and in different districts.

The meteorological observations at Plymouth Navigation School, carried on for a period of more than twenty-six years by Dr. J. Merrifield, ceased on his death in June last. It seemed desirable that Plymouth should not be without an observing station, and as the Association was undertaking other work of a similar nature it was decided to begin observations on the scale of a station of the second order.

Ashort time ago I received from my friend Mr. J. T. Cunningham a Cephalopod which had been taken by a trawler in the neighbourhood of Plymouth, with the remark that it appeared to fit well with the description of Ommastrephes eblanæ (Ball) as given by Forbes and Hanley, and that it undoubtedly belonged to the genusIllex of Steenstrup.

On the Occurrence of the Nudibranch Hancockia at Plymouth.—I am glad to be able to record a second English specimen of this interesting form. It was dredged, apparently on Delesseria, in Plymouth Sound, about halfway between Drake's Island and the west end of the Breakwater, on August 20th, 1891.