hetioeen the Spongiadce and the Foraiainifera. 353 



Although, however, tlie spongozooii is a flagenated infiisorian 

 possessing, so far as has yet been shown, no further organs tlian 

 those mentioned, still, for all that we know, it may be as com- 

 plicated as an elephant, whose trunk, liver, and bladder could 

 alone be seen through the general transparency of the body. 



In these matters minuteness goes for nothing. Size, light, 

 darkness, motion, tenuity, &c. are only relative in degree; 

 and the degree to Avhich we can appreciate them depends 

 upon the power of our brains respectively, tvMch is limited. 



That mind (taken in its general sense) alone can com- 

 prehend any thing beyond the power of the brain, which 

 builds up the whole of the body and permits a portion of itself 

 to be used by the brain it has developed, bearing a relation to 

 the latter somewhat similar to that Avhich steam bears to a 

 steam-engine. 



Thus, in the philosophy of the Buddhists, the mind does not 

 perish with the brain ; while Christianity promises a resurrec- 

 tion of iho. flesh. 



But to return to our immediate subject, as this digression 

 is merely to show that we should not deny or affirm that 

 which is beyond the power of our brains to comprehend. 



We come, now, to the skeleton of the Spongiadee and tlie 

 Foraminifera respectively ; and here the differences are most 

 manifest, inasmuch as the skeleton of the former is inside^- 

 while that of the latter is outside. 



The sarcode of the sponges hangs upon their skeleton as the 

 flesh of a human being hangs about his bones ; while the 

 sarcode of the Foraminifera lives inside its skeleton after the 

 manner of a snail, only making its exit through holes all over 

 its shell or test, in which generally, if not always, there is one 

 principal opening, leading directly outwards from a single- or 

 many-chambered interior, in accordance with the simple or 

 complicated form of the species. Of course by the term " ske- 

 leton" I mean the organ of support. 



The materials, too, of which the skeleton is composed are 

 arranged differently. Thus, in the sponges the proper spicules 

 (that is, the spicules formed by the sponge itself) have, in all 

 instances with which I am acquainted, their points directed 

 outwards, one object of which is no doubt for the better holding 

 on of them by the sarcode, and another defence, as spines 

 upon a hedgehog's back ; while in the test of the Foraminifera, 

 where spicules are present on the surface, both heads and points 

 are directed outwards indiscriminately. 



This is particularly well shown in Squamulina scopula and 

 its branched variety ('Annals,' vol. v. p. 309, pis. iv. & v., 

 May 1870, and vol. vi. p. 346, Oct. 1870), together with the 



An7i. & Mag. N. Hist. Ser. 4. Vol. xi. 23 



