2J4 LUCEKx\AlUJ3 AND THEIR ALLIES. 



divided into three distinct portions (A), we have never been able to find a true, 

 undoubted cell-multiplication. Tlie peculiar disposition of the contents is as sin- 

 gular as the modifications of the wall ; and it seems to be strictly in accordance 

 with the latter. It would appear that the same influence which produced the 

 annular semipartitions also affected the dark, innermost, pigment mass (d) in such 

 a Avay as to constrict it exactly opposite these annuli ; but yet not by the direct 

 impression of the latter npon the former, for a considerable clear, transparent layer 

 (d-), forming the periphery of the contents, intervenes. If, therefore, there is any 

 impression transmitted it must be through the latter layer. Laying aside, now, 

 this rather mechanical, physico-motor explanation, which we have used merely as 

 a matter of convenience, and not to illustrate any real series of sequences, which 

 might be supposed to arise the one from the other, we will state, in brief, our con- 

 viction that the cell-contents have, by an inherent property, assumed the subdivided 

 form which is presented there, and that the annidi of the wall are rather formed 

 last, and probably deposited from the surface of the contents. 



211 (A^. As we recede, now, toward the entrance to the cavity of the coUeto- 

 cystophore, we actually advance toward an explanation of the nature and origin 

 of these singular contents. Gradually the layer grows less and less in thickness 

 (A to D), and the component cells decrease at a corresponding rate in depth. But 

 we particularly note that the annular semipartitions gradually lower their ridges, 

 and the constrictions grow shallower until botli disappear by the time we arrive at 

 those cells Avliich are about as deep as they are broad (D). The innermost dark 

 pigment mass yet consists of very large, closely-packed, irregular granules, but 

 rather smaller than in the thickest part of the layer. From this point, still 

 receding, the dark mass grows proportionally less, and the clear contents corre- 

 spondingly greater {fig. 95, (p), while the cell bodily shallows down to near the 

 proportion of dermal epithelium (C). In the latter condition the dark pigment- 

 mass appears, in a profile view, like a thin streak in the middle of the cell, but in 

 an end view it has the appearance of an irregular nucleus {fig. 95, d"), being in 

 reality nothing more nor less than a nucleus covered by a coating of pigment- 

 granules, as we have described in the ectophragma (^ 191) and other places. 

 Now, if there be any part of the cell that influences internal changes more than 

 another, it certainly is where the nucleus usually appears ; and we consider the 

 nucleus to be the expression of an intensified concentration of cell-power, and 

 not an isolated body, as it is usually described. When, therefore, the dark pig- 

 ment mass accumulates in all the intervening space between the nireleus and the 

 extremities of the cell cavity, we do not suppose that it gradually thickens as a 

 coating over the nucleus, by any condensing power of the latter; but that it 

 develops in mass under the all-pervading cell-power which radiates, as it were, 

 from one point of greatest intensification. In this way we may explain the final 

 appearance of the constriction of the dark mass, and the annular semipartitions of 

 the wall. These peculiarities could no more be produced by the operations of an 

 isolated body at a distance, a self-contained nucleus, than could the analogous 

 changes which eventuate in the appearance of the spiral coil of the nematocyst 

 {Jujs. 13D-U5). It will be apparent enough, without further explanation, that 



