330 • REPOKT— 1864. 



of nearly 500 feet, these mollusks, which are ground-dwellers and have no 

 means of rising to the surface of the sea, could not have floated in this way, 

 or even had time or an ojijiortunity, since they were taken up from the depths 

 of the ocean, to acquire such a habit. Was it instinct ? If so, when was 

 it implanted ? Another fact worthy of notice is the eagerness which they 

 displayed to escape out of the water and to breathe the open air. One would 

 have supposed that the water at the bottom of the ocean was much less 

 aerated or oxygenated than that on the shore, and that the mollusks would 

 have supplied their gills more copiously in surface-water with the requisite 

 element. But exactly the contrarj' has been ascertained by some experiments 

 conducted on board the Prench surveying-ship ' Bonite ' ; and it is now 

 clearly established that the quantities of atmospheric air increase with the 

 depth. According to Dr. Wallich, in an admirable chapter of his ' North 

 Atlantic Sea-bed,' entitled "The Bathymetrical Limits of Life in the Ocean," 

 the proi)ortion of gaseous matter taken up bj water is very greatly increased 

 under an increase of pressure, all gases (especially oxygen and hydrogen) 

 being easily compressible and becoming fluid iiuder a comparatively slight 

 pressure. We but imperfectly understand the mode in which the solution of 

 atmospheric air in sea- water is brought about; but the tendency of fluids to 

 absorb gaseous bodies is constant under all circumstances, and the quantity 

 which they are capable of appropriating increases with pressure. It therefore 

 follows that the deeper the stratum of water, the greater mi;st be the amount 

 of gaseous matter held in solution by it. For a more detailed explanation of 

 this problem I must refer to the work above cited. I can now understand 

 why deop-water moUusks do not find in the surface-water the same supply 

 of atmospheric air as they had been accustomed to, and why they creep out 

 of it into the open au- to avoid a sensation which we should call stifling or 

 suffocation. 



I ^vill conclude with extracts from the works of two great and pleasant 

 writers, which relate to the subject-matter of this Report. We wiU first hear 

 Professor Edward Forbes : — 



" I can speak personally as to the pleasure of such explorations, the more 

 to be esteemed since in these days there are few coimtries so entirely new as 

 to warrant the traveller's boast that he is the first educated man to visit 

 them and to discover their wonders. But beneath the waves there are many 

 dominions yet to be visited, and kingdoms to be discovered ; and he who 

 venturously brings up from the abyss enough of their inhabitants to display 

 the physiognomy of the country wiU taste that cup of delight, the sweetness 

 of whose di-aught those onlj who have made a discovery know." (' The 

 Natural History of the European Seas,' p. 11.) 



Professor Kingsley comes next and last. He says, with equal truth, 

 that there is a mysterious delight in the discovery of a new species ; but he 

 thinks "the pleasure is too gi'eat; that it is morally dangeroiis, for it brings 

 with it the temptation to look on the thing found as yovu' own possession, aU 

 but your own creation ; to pride yourself on it, as if God had not known it 

 for ages since, — as if all the angels in heaven had not been admiring it, long 

 before you were born or thought of." (' Glaucus,' p. 28.) 



Description of a Neiu Species o/ Amphisphyra*. 

 AMPHispnTRA EXPANSAf, Jcflreys. 

 Body gelatinous, clear white, sprinkled aU over with minute black specks. 

 * Shaped at both ends like a mallet. t Spread out. 



