July X2, 1877] 



NA TURE 



205 



method of observation — following a single form through 

 all the phases of its life — has never been thoroughly 

 adopted ; and conflict of interpretation inevitably arises. 

 Biitschli has fallen into the same groove, and his results, 

 although valuable and full of suggestion, have no irre- 

 sistible meaning. They present points of new departure 

 for h; pothesis, and nothing more. 



Nor can we be quite certain, from the evidence afforded, 

 of the correctness of the larger and more important of 

 the facts stated. We want, for example, more than a 

 mere statement that the " ciliary apparatus " and the im- 

 portant organs of the peristoma were actually destroyed by 

 conjugation. That they are suppressed — flattened — de- 

 ranged by prolonged contact, we have observed again 

 and again in several forms, especially Styloiiichia, Pustit- 

 lata, and Mytilus : but they rapidly regained their normal 

 condition, and certainly did not grow afresh by " reju- 

 \enescence " as in the cases stated by our author. And 

 this is certainly of moment. In some important sense 

 also this will apply to the nucleus and nucleolus themselves. 

 Doubtless the investigations of Biitschli on the metamor- 

 phoses of these bodies, especially the latter, in such forms 

 as P. bill sarin, aurelia,pitlri)ium, and others have a large 

 importance ; and if they should be confirmed by con- 

 tinuous observation on the living form, controlled by the 

 evidence of preparation"^, made at short intervals, under 

 the influence of acetic and osmic acids, and other reagents, 

 not onl) will Balbiani's hypothesis become modified, but 

 a sequence will bo • iven to the successive stages, often 

 now wanting, in tin.; observations of Biitschli himself It 

 is impossible not to be struck, for example, with the 

 minuteness of his observations, made on the nucleolus 

 changes in P. biirsaria ; but they are utterly incompetent 

 to accomplish his own purpose and establish his own idea. 

 He declares that both Balbiani and Stein utterly mistook 

 the destiny of the nucleus and nucleolus ; and quite re- 

 pudiates the changes said to come upon the nucleus 

 during conjugation. But to establish his own hypothesis 

 the whole process of morphological change in the nucleus 

 at least should have been followed, and not once but many 

 time?. Vet the very first complete change effected in this 

 organ could not be explained ; and after following it into 

 fission as the result of conjugation, he observed four 

 " nucleolus capsules " as the issue, in each param:ccium. 

 Two of these became light and clear ; the other two di- 

 minished in size, and became fibrous, but on the second 

 day they lost their fibres and became homogeneous and 

 dark ; and on the third day — vanished .' that is to say, by 

 the method pursued by the observer, they were lost, and 

 " no trace of them was to be four d." From this Biitschli 

 concludes that they were " cast out," and no further con- 

 cern in relation to them is evinced ! Vet it must be re- 

 membered that Balbiani describes a similar condition of 

 the same forms, and considers the granules germs or ova. 

 To deal thus lightly with the ejection of apparently or. 

 ganised bodies in a set of observations designed \.o prove 

 that what have been considered ovarian, or at least sexual 

 products, was erroneous, is certainly remarkable. Clearly 

 no result can be arrived at until the manner of the 

 vanishing of these bodies be understood ; and if they 

 were ejected, until their future destiny became known- 

 This is all the more imperative from the fact that after 

 the ejection of the " bodies," the paramscium resumes its 



normal condition in size and appearance, although the 

 method by which this conclusion is reached is by saltative 

 inferences, and not by continuous proofs. 



Again, — in B. biiisaria and a/ireiia, two " light bodies " 

 — definite products of the nucleolus — are repeatedly seen 

 in successive stages after conjugation, but having been 

 followed to a certain point we are told that " the further 

 destiny of these two light bodies escaped me ! " and yet it 

 is assumed that the life history of the creatures is known. 



Again, — in these same forms the nucleus broke up into 

 a hundred spherules ; and yet cur author frankly declares 

 " 1 am not quite certain of the destiny of the . . . frag- 

 ments of the old nucleus !" This is the more important 

 since Schaafhausen affirms that he has seen P. aurelia 

 lay or deposit ova ; " the organisms crammed full of egg- 

 spheres, surrounded with clear fluid, extrudes in an hour 

 several times one such egg." 



Again, — in Colpidium colpoda, after conjugation, two 

 small light spheres appear, these the author "thinks 

 most probably " grow out of the nucleus capsules, while 

 the «/cr/t'«j- itself is cast outj Biitschli followed it " for 

 some time" and then it was lost, so he does not know its 

 final destiny ! Of what service can all the subsequent 

 transformations of the organism itself be when this ejected 

 organism is assumed to mean nothing.' In Blepliaiisma 

 Iiiterita a number of "' nucleolus- like bodies " were found 

 by '' squeezing and acetic acid," but their destiny was 

 never found ; while on the third day after conjugation 

 " the nucleus which had been present up to this time was 

 not to be found," and so the author meets the emergency 

 by supposing that it was " cast out," and of course had no 

 meaning in the history of the organism. So also in 

 Cliilodon cucidus, we are told that the " destiny of the 

 original nucleus remains undetermined." In the conju- 

 gation phenomena of Stylonichi mytilus there is an equal 

 or even more grave defect. 



In precisely the same way in the attempt made by 

 Biitschli to establish the position he occupies that the 

 embryonal regions of Balbiani and others as existing in 

 these lowly forms are to be entirely explained by the pre- 

 sence of swarm spores of internal parasites, there is the 

 same want of perfect sequence, and the unscientific " no 

 doubt" which is made to supply the place of facts. 



But our space is exhausted. We have not referred to 

 the above defects with any attempt to depreciate a valu- 

 able book. It is because it is strong enough in important 

 facts to be a help in the unravelling of biological diffi- 

 culties that we have not hesitated to point out the differ- 

 ence between the theories and the facts which it contains. 

 To have attempted exhaustive criticism of such a work 

 would have involved four or five times the space occupied 

 by this article ; but after a careful perusal and reperusal of 

 its contents, we are obliged to admit the ingenuity of the 

 author both in the work he has done and the method he 

 has employed for interpreting it. But it is to the former 

 that we attach by far the most importance ; for whilst 

 there are many missing links in evidence which make 

 conclusions from the whole unwise, there are facts given 

 us which nmst help future observers and land us nearer 

 to the desired truth. 



It may be finally observed — i. That if the theory of 

 rejuvenescence, as put and insisted on by Biitschli, be 

 established for any one form, conjugation should have no 



