150 MAJOB OTFEN OlSr THE STJErAOE-I'AiriS'A OP MID-OCEAIT. 



it desirable that tliey should be brought together and made into 

 a separate and what appears to me to be a natural family, for 

 which I propose the name of Colymbitee*. 



This family, then, will include two genera that, perhaps, ought 

 never to have been separated, as their affinities are strongly 

 marked, and their habits, and probably their structure, differ 

 from those in the other forms of the Poraminifera. 



Their having the power of rising to the surface surely shows 

 that the animal must have some special means or organs adapted 

 to this purpose ; although they may not be distinguishable at pre- 

 sent to our observation, the fact, I think, may be taken for granted. 

 This family of the Foraminifera may then be considered to be the 

 most nearly allied to the Polycystina, which, as I have before 

 proved, are frequenters of the surface of mid-ocean. 



Observation may yet show us the means used by both to enable 

 them to rise and sink at pleasure. I may here mention that the 

 AcantliovietrcB appear to have the same power and habits ; and we 

 may therefore infer that all these Ehizopods have some portion of 

 their organization in common: I am not yet prepared to say 

 whether or not all the recent known Polycystina may be found on 

 the surface. 



Dr. "VVaUich, in his work on the ' North Atlantic sea-bed,' does 

 not appear to be able to prove quite satisfactorily that the Glohi- 

 gerincB which he succeeded in getting from the bed of deep por- 

 tions of the ocean were absolutely alive at the time taken ; for he 

 has the following passage at page 136 : — " Under the most favour-' 

 able circumstances and only after the lapse of considerable time 

 do the shallow-water forms, when in captivity, exhibit pseudo- 

 cyclosis or extend their pseudopodia ; and hence, since it is in the 

 last degree unlikely that those brought up from extreme depths 

 should present these evidences of vitality, we must rest content with 

 collateral proofs: fortunately these are of a very satisfactory kind." 

 ]jVom this it will appear that the rising of these shells from the 

 bottom after they have once fallen to it, is not yet satisfactorily 

 proved. 



That Dr. "Wallich does not consider the GlobigerincB to be dis- 

 tributed through the waters of mid-ocean the following quotation 

 from his work wiU show ; and from it will be seen likewise that 

 their shells are found as universally distributed at the bottom as 

 I have proved them to be on the surface. " The minute calcareous 

 shells of the Eoraminifera are the most frequent and widely dis- 

 * From Ko\vfi(37]n)s, a divei". 



