34 THE POPULAR SCIENCE MONTHLY. 



gerince and otlier Forcmilnifera y;h\Qh. are found in the deep-sea mud, 

 live at the great depths ia which their remains are found ; and he sup- 

 ports this opinion by producing evidence that the soft parts of these 

 organisms are preserved, and may be demonstrated by removing the 

 calcareous matter with dilute acids. In 1857 the evidence for and 

 against this conclusion appeared to me to be insufficient to warrant a 

 l^ositive conclusion one way or the other, and I expressed myself, in 

 my re|>ort to the Admiralty on Captain Dayman's soundings, in the 

 following terms: 



""When we consider the immense area over which this deposit is spread, the 

 depth at which its formation is going on, and its similarity to chalk, and still 

 more to the marls of Caltanisetta, the question, 'Whence are these organisms 

 derived? ' becomes one of high scientific interest. 



'C^ 



" Three answers have suggested themselves : 



"In accordance with the prevalent view of the limitation of life to compara- 

 tively small depths, it is imagined either : 1. That these organisms have di-ifted 

 into their present position from shallower waters ; or 2. That they habitualiy live 

 at the surface of the ocean, and only fall down into their present position. 



" 1. I conceive that the first supposition is negatived by the extremely marked 

 zoological peculiarity of the deep-sea fauna. 



"Had the GloMgerincB been drifted into their present position from shallow 

 water, we should find a very large proportion of the characteristic inhabitants 

 of shallow water mixed with them, and this would the more certainly be the 

 case, as the large GloMgerinw^ so abundant in the deep-sea soundings, are, in 

 proportion to their size, more massive and solid than almost any other Foi'a- 

 minifera. But the fact is, that the proportion of other Foramimfera is exceed- 

 ingly small, nor have I found as yet, in the deep-sea deposits, any such matters 

 as fragments of molluscous shells, of EcTiiniy etc., which abound in shallow 

 waters, and are quite as likely to be drifted as the heavy Globigerince. Again, 

 the relative proportions of young and fully-formed Globigerhice seem inconsistent 

 with the notion that they have traveled far. And it seems difficult to imagine 

 why, had the deposit been accumulated in this way, Cosciiiodisci should so 

 almost entirely represent the Diatomacem. 



"2. The second hypothesis is far more feasible, and is strongly supported by 

 the fact that manj Poly cist inecB (Badlolaria) and. Coscinodisci are well knov^n 

 to live at the stu-face of the ocean. Mr. Macdonald, Assistant Surgeon of 11. M. 

 S. Herald, now in the Southwestern Pacific, has lately sent home some very val- 

 uable observations on living forms of this kind, met with in the stomachs of 

 oceanic moUusks, and therefore certainly inhabitants of the superficial layer of 

 the ocean. But it is a singular circumstance that only one of the forms figured 

 by Mr. Macdonald is at all like a Globigerina, and there are some pecuharities 

 about even this which make me greatly doubt its affinity with that genus. The 

 form, indeed, is not unlike that of a Globigerina, but it is provided with long 

 radiating processes, of which I have never seen any trace in Globigerina. Did 

 they exist, they might explain what otherwise is a great objection to this view, 

 viz., how is it conceivable that the heavy Gloligerina should maintain itself at 

 the surface of the water? 



" If the organic bodies in the deep-sea soundings have neither been drifted, 

 nor have ftiUen from above, there remains but one alternative they must have 

 lived and died as they are. 



