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1. At first spiracle, .
first dorsal, .
0 10 5 point of snout,
0 3 Angle of mouth to insertion of pectoral fin,
17 Angle of mouth to first spiracle,
09 Length of group of spiracles, .
0 51 “The colour was a uniform light-bluish grey, skin covered with minute hooked spines, hooks pointing backwards. A row of mucous ducts extended froin the tail to the head, their apertures, four-tenths of an inch apart, forming the lateral line which branches off at the head into symmetrical curves. These ducts are about half an inch in length, and communicate obliquely with a longitudinal canal just under the skin, lined with a dark pigment membrane. On dissecting the fish, the liver, consisting of two lobes, each 5 feet in length, weighed 35 pounds.
intestine to first cæcum,
Thence to first turn,
i 11 “ In the stomach was found a pultacious mass, along with portions of the cat-fish, cod, and haddock, and a large cod-hook with a part of snood attached. The usual spiral valves were observed in the intestine. The claspers at the base of the ventral fin showed this to be a male fish; and an elongated testis, covered by a delicate membrane, extended on each side of the spinal column the whole length of the abdominal cavity. Some of the more interesting portions of the viscera are now in good hands,- Mr Turner, who was present at the dissection, having possession of
those parts which were considered worthy of more critical examination.
"Three years since, in the month of May, a somewhat larger specimen than this was caught near Inchkeith, and is now preserved in the Natural History Museum, University."
In continuation of previous observations made during the course of the last three or four years, reported annually to the Society by this Committee, the Convener examined continuously the herrings and sprats brought to market during the whole fishing season, and the result has shown that, from the end of June to the end of September, and from the beginning of December to the beginning of March, herrings were taken having spawn in all stages of development, and the proportion of herring fry found among the sprats was even smaller than on previous occasions,—so far as observed, certainly not five per cent. on an average,—thus supporting the deductions drawn in previous Reports of this Committee. The Pilchard, or Gipsey herring, appeared along with the true herring occasionally or for short periods during the winter, and about the month of February large numbers of the sea bream were taken in the Firth.
A vote of thanks was given to the Committee.
VIII. On the Composition of a Pseudo-Steatite. By Murray Thomson,
M.D., F.C.S., Lecturer on Chemistry, Edinburgh, and Mr Mord
The mineral which is the subject of this short notice I have ventured on denominating a Pseudo-Steatite; it was found by John Gellatly, Esq., late of the Chemical Works at Bathgate, forming a joint between the masses of a kind of serpentine ; which latter rock is esteemed of some value for the construction of certain parts of bakers' ovens, and for which purpose it is quarried close to the village of Blackburn, Linlithgowshire.
Mr Gellatly, while making a visit to this quarry, picked up some pieces of the mineral, and sent them to my pupil, Mr Mord Binney, simply with the view of furnishing material to him for analytical practice, and not at first under any impression that the result of analysis would reveal anything unusual. Mr Binney proceeded with the analysis under my direction; and it was only on the completion of it, and inspection of the results, that Mr Gellatly and myself were struck with the disagreement that seemed to exist between the external characters of the mineral and its chemical composition. As it presented the external characters of a steatite, it was regarded by all who examined it to be a variety of that mineral; but the analysis showed it to contain only a comparatively small quantity of magnesia, which is the characteristic base of the steatites, while at the same time, the alumina had a high percentage ; in other minor features, also, the composition did not correspond with any of the published analyses of steatites.
Having arrived at this result, it was needful, to avoid error, to make fresh analyses, which were accordingly made by Mr Binney and myself independently, and the numbers thereby obtained are those which have been put below side by side with each other. The result of these second analyses in a great measure confirmed the first, though they showed a composition widely different from that of steatites generally.
The typical composition of a steatite is, that it consists of silica, magnesia, with more or less water: these are the usual constituents enumerated; but it will be seen that the mineral we have analyzed differs from that type in containing but little magnesia, a good deal of alumina, and protoxide of iron; along with a diminished percentage of silica. There is, however, one variety of steatite, called by Haüy “saponite,"* which, by both Klaproth's and Swanberg's analyses, contains considerable amounts of alumina as well as magnesia; but even here the quantity of the former base does not exceed 10, and that of the latter is not set down as less than 25 per cent. To neither of those numbers do the percentages which we obtained approach ; so that from the composition of the mineral, coupled with the following physical characters, we are inclined to think there are sufficient grounds for concluding that it is a new species.
* Dana, Ed. 1850, p. 253.
The following are the physical characters of the mineral:It occurs in irregularly striated masses of a dark-green colour, which here and there changes to a brownish tint; it has generally a dull surface, and when exposed to the air effloresces; fracture uneven; it is easily broken and reduced to powder, which has a green colour. Every part of the masses has the genuine soapy feeling of the steatite. Its degree of hardness is 2.2; as it is hardly scratched by gypsum, but is distinctly so by calc spar. Streak dark greenish grey, and sublustrous. It does not adhere to the tongue, has no taste, but has a slightly argillaceous odour, especially when a fresh surface is exposed. The specific gravity is 2.469. Before the blowpipe it is infusible, but changes in colour from green to brown ; with borax a yellow head changing to green; with carbonate of soda a persistent dull green.
The results of our analyses are now appended.
IX. Notice of a Fætal Narwhal (Monodon monoceros, Linn.) By
Robert Brown, Esq.
Mr Brown exhibited a small fætal specimen of a Narwhal (Monodon monoceros, Linn.); and stated that another foetus was also found in the uterus of the same animal, which was captured in Davis' Strait, June 23d, 1861.
In the “Linnean Transactions” (vol. xiii. pp. 620, 621, “ Extracts from Minute Book”), in a letter from Mr W. R. Whatton of Manchester, it is noted, that in the summer of 1821, while a Hull whale ship was beset in the ice in the VOL. II.
448 Proceedings of the Royal Physical Society.
Mr W. S. Young proposed a vote of thanks to the Presidents and other office-bearers, which was unanimously agreed to, and the Society adjourned until the commencement of the next Session.