268 -' • -BULLETIN OF THE 



when the centre of the nucleolus is in focus. The granules of the"Eorn- 

 chenschale " are separated from the surrounding network by a homogeneous 

 space, so that a direct connection between the network and " Kornchenschale " 

 cannot be made out except in rare cases, as when the granules are hardly dis- 

 tinguishable from those of the network. In such cases the granules of the 

 " shell " are also directly united to each other by filaments. 



An exceedingly fine protoplasmic network in the body of the cell (ciliate epi- 

 thelium) is in connection on the one hand with the cilia, and on the other hand 

 sometimes (gills of Axolotl) appears to be in continuation with the nuclear net- 

 work (p. 116). The objects which Eimer has figured are principally ciliate epi- 

 thelium from the mouth of Salamandra, the gills of Siredon and Anodonta, 

 and certain ectoderm cells of Trachymedusee. The first glance at some of the 

 figures is enough to raise at once the question, if these appearances are not 

 really due to phases of nuclear division ; or, to be more exact, if the " Korn- 

 chenkreis " is not after all identical with the well-known " Kernplatte." The 

 possibility of such an equivalency has not escaped Eimer himself (p. Ill), but 

 an attempt to explain how the " Kornchenschale " may be harmonized with 

 the " Kernplatte,'rand the radial fibres with the spiiidle'.. fibres^ is- not' madey 

 and there are many reasons to interfere with the establishmeaitpfisuch axom-( 

 parison. If Elmer's descriptions permitted one to ; suppose that the granules 

 of his " KornchenA;ms " were limited to a single plane, as that name naturally 

 implies, an important objection would be cancelled ; but they do not. If it 

 were permitted to suppose — which it is not — that the central nucleolus did 

 not occupy the same plane as the granules of the " Kdrnchenkreis," one might 

 identify the radial fibres of Elmer's description with the "projected" spindle 

 fibres, and his " nucleolus " with one of the poles of the spindle. Further, 

 such an identification would necessarily compel its extension to those wheel- 

 and-spoke figures, several of which are represented as occurring in a single 

 nucleus (see Figs. 6, 9, and 10, op. cit). I am unable to recall a parallel case 

 of multiple spindles to place beside it. Perhaps the very recent studies of 

 Flemming ('78^) will be sufficient to make more intelligible the relation of 

 " Kornchenschale " and " Kernplatte." 



In a note Flemming ('77) communicates the fact that he has observed the 

 nucleoli and the nuclear network, previously described by him, in the living 

 and uninjured larvce of salamanders, so that the inference possibly to be drawn 

 from the studies of Langhans, viz. that these phenomena are all post-mortem, 

 is in no way justified. These conditions were observed on nuclei of connective 

 tissue in the tail, the nuclei of nerve cells, nuclei of red blood corpuscles, 

 etc. In the living condition, however, the structure is pale, and only to be 

 seen with good light, a fact that may explain the account of Langhans. More- 

 over, the use of reagents may produce shrivelling and coagulation ; neverthe- 

 less, the substantial identity of the fresh and hardened conditions cannot be 

 called in question. 



Stricker ('77) not only recognizes the existence of a reticulum in the nu- 

 cleus, but has directly observed an amoeboid motion of its filaments which he 



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