172 



germination through the inner arch of small apertures : they are 

 usually of a paler and more transparent aspect than those of older 

 growth ; but I have never yet seen any in process of formation. 

 Sometimes| the cells continue gradually to increase in size with sym- 

 metrical uniformity, when suddenly one of them is found to have been 

 arrested in its development, not attaining to more than half its proper 

 dimensions ; and the new ones subsequently added are regulated in 

 their increase of size, not by those which had previously attained to 

 their full development, but by the one which has been so stunted, — 

 from the contracted form of which the cells again continue to grow 

 and increase in regular order ; only being thrown back, as regards 

 their size, by almost an entire convolution. This shows that the 

 budding, if such it be, takes place from the part of the septum nearest 

 the centre, and most probably through the small oral orifices, — the 

 formation of the calcareous covering being the result of a process 

 which goes on subsequently to the development of the soft tissues 

 intended to constitute the future articulation. 



It is scarcely necessary to add that the preceding details also show 

 the inapplicability of the generic character of Polystomella, as given by 

 M. D'Orbigny, to the subject of this memoir. It is only when one or 

 more of the outermost chambers is broken away, exposing to view the 

 front of one of the internal septa, that we find anything agreeing, even 

 in appearance, with his description : it is certain that the "fossettes" 

 have no sort of connexion with the true oral (?) orifices. 



In an early portion of this memoir I alluded to the possibility of 

 effecting some improvement as to the relative position in the scale of 

 animal organisms which M. Ehrenberg thinks the Foraminifera 

 ought to occupy. In the communication which he laid before the 

 Berlin Academy in 1838, he came to the conclusion that they ought 

 to be classed with the moss-corals {Bryozoa ?), and the ' Philosophical 

 Magazine' for 1841 contains his new classification of the Bryozoa, 

 in which they are included, being only separated from the highly- 

 organized cilio-brachiate Bowerbankia and their allies by his order 

 Gymnocorce, containing the genera Cristatella and Zoobotryon. In 

 his memoir read to the Academy in January, 1840, after he had made 

 additional observations on his specimens from Cuxhaven, he says, 

 " The other characters already communicated to the Academy in 1838, 

 together with the position in the natural kingdom there given, are only 

 confirmed and established by these subsequent observations." — 

 (Taylor's ' Scientific Memoirs,' vol. iii. p. 344, 1842). 



This classification is of course a great improvement upon those of 



