304 Dr. Wallich [Jan. 25, 



recent condition, affords no proof, inasmuch as the great quantity of 

 saline matter present in sea water, and especially at great depths, would 

 of itself alone account for their perfect state of preservation. 



" During the recent survey of the North Atlantic, I found that in 

 certain localities, where the Globigerina deposit was of the purest kind 

 and in the greatest plenty, the specimens from the immediate surface 

 stratum of the sea-bed alone retained their normal appearance, both as 

 regards the perfect state of the sarcodic contents of the shells and the 

 presence of the pseudopodia. The latter organs were never seen by 

 me in an extended condition ; but in the specimens alluded to, and in 

 those only, occurred as minute bosses, resembling in shape the rounded 

 rivet-heads on boilers, closely appressed to the external surface of the 

 shell ; whereas, in specimens from the substratum, the colour was much 

 duskier, and these bosses were absent. And further, in these pure 

 deposits the shells were to be found in every gradation, from the single 

 chamber, of microscopic minuteness, hyaline transparency, and extreme 

 thinness, to the dense Zeolite-like structure of the many-chambered 

 mature shells, which are large enough to be readily distinguished by 

 the naked eye. These facts, when taken in conjunction with the entire 

 absence of the varied remains of other organized structures found in 

 localities where the Globigerinae are only scantily represented, afford, 

 as I conceive, all but the direct proof, which can only be arrived at 

 on witnessing locomotion, or the protrusion and retraction of the pseu- 

 dopodia of the organisms in question. 



'' Most fortunately, as it happened, this collateral evidence was ren- 

 dered doubly conclusive by other proofs of a most unexpected and 

 interesting kind. Before entering on these, I may state that the sub- 

 stratum, spoken of as differing in aspect from the immediate surface- 

 layer, is nevertheless identical in composition ; the difference in colour 

 arising simply from decay. It contains no living Foraminifera ; for 

 the minute particles of matter becoming gradually condensed and 

 aggregated together by molecular affinity, and the enormous super- 

 incumbent pressure exerting itself only in one direction, that is, verti- 

 cally, its permeability by fluids is thus completely destroyed, and it is 

 compacted into a dense mass of far too unyielding a nature to admit 

 of its being traversed by living creatures of any kind. As the Forami- 

 nifera die off, their shells and decaying contents, together with the 

 minute particles of amorphous matter associated with them, go to 

 build up the calcareous strata of the earth's crust. I would mention, 

 that in order to determine whether the Globigerince live as free 

 floating forms in the mid strata of water, I attached a small open- 

 mouthed bag, at about 200 fathoms from the extreme end of the 

 sounding line, in a locality where the species was most abundant in the 

 deposit, and brought it up through nearly 5000 feet of water without 

 securing a single shell. 



" But by far the most important and interesting discovery remains to 

 be noticed, namely, the detection of a high order of radiate animal, in a 

 living state, at a depth'of a mile and a half below the surface of the sea. 



