NOTES AND QUERIES. 161 



Fragment on Submarine Zones oe Distribution. — 1. As soon as the 

 main facts of the distribution of animals and plants into regions and districts, 

 and into zones of elevation above the sea-level had been generally established, 

 it was assumed that like limitations held good as to marine plants, and (as in- 

 separable from them) to zoophytes. 



2. It was thus laid down pretty positively that the coral animals could not 

 exist at certain depths ; and from these the inferences that coral formations, 

 per se, could have no great thickness unless submerged whilst in progress by 

 the sinking of the ground on which the animals had attached themselves as a 

 nucleus or basis ; and if this progress were carried on slowly the said animals, 

 within " regulation limits" as to depth, could continue their work upwards as 

 before. 



2. In Darwin's valuable work on coral formations, p. S5, he gives certain 

 tabulated data of the known depths at which corals have been found alive. The 

 example most to my purpose (for I am unacquainted with " Cellepora" found 

 at one hundred and ninety fathoms) is " Gorgonia, or an allied form," at one 

 hundred and sixty fathoms deep. 



4. The pressure at one hundred and sixty fathoms (taking sea-water at about 

 sixty-five pounds per cubic foot) is four hundred and thirty-three pounds per 

 square inch ; and who that is at all familliar with the exquisite delicacy of 

 structure in the polyp of gorgonia of any kind can suppose that mere internal 

 counterpoise of warer within to water without would render life possible in 

 such types of all that is tiny, frail and fairy -like ? No wood sunk to that depth 

 would ever float on being drawn up to the surface : it would become " water- 

 logged." Hence it is conceived that nothing but the mysterious agency of 

 vitality can give the tissue its power of resisting the above mentioned and 

 very considerable penetrative pressure. "Who then is to limit the depth at 

 which zoophyte life is to be found, and coral-reefs to be carried on ? 



5. Such being the case at one hundred and sixty fathoms, what are we to 

 say to the facts given in Mr. G. E. Roberts' interesting paper — " High and 

 Low Life" — in which the existence of Ophiocoma, &c, is traced to a depth of 

 two miles, or eleven times the said one hundred and sixty fathoms ? 



G. It was ever to my mind an unproven verdict (or rather dictum) that laid 

 down such strict analogy between the zones of distribution for terrestrial vegeta- 

 tion, and their assumed correspondents as regards marine plants and animals 

 (especially the latter) ; as if they were the anamorphic reflections downwards 

 of the terraced arrangement of zonal regions upwards, shown on the surface of 

 the sea. 



7. In earlier days I was once honoured with a slight, but " free and gentle" 

 passage at arms — a sort of holme-fight — with one of our largest Oxodons, or 

 Cantabnodons (we say not whichj, fresh from his native fens and reeds, who 

 had taken post on this sandbank position, and in spite of every logical instinct 

 on the pourquoi non ? footing I presume, required me to prove a negative 

 thereon. Strange to say, he was an eminent mathematician. What would he 

 have said on seeing his sunderbund-hypothesis utterly dispersed by the facts of 

 Dr. Wallich and Mr. Darwin ? 



8. It may be assumed, safely enough, that coral formations may spring from 

 around any suitable nucleus in the very floor of the ocean ; though not by any 

 means restricted from starting their characteristic contours and belts from around 

 the upper portions of submarine hills — working from thence upwards as from 

 an advanced base of operation..— R. J. Nelson, R.E., Halifax, Nova Scotia. 



Skeleton of a Nondescript Animal pound at Buenos Ayres. — (Vol. iv, 

 p. 18). — I refer your correspondent who asks what scientific account has been 

 given of the great animal preserved in the Madrid Museum, to Dr. Buckland's 

 Esssay in the Bridgewater Treatise. The skeleton which is that of the Mega- 



[ SUPPLEMENT TO THE " GEOLOGIST," No. 40.] 



