2 6o PROTOPLASM 



tion certainly did not depend on the arrangement of the yolk 

 granules, but that it was a " transitory " protoplasmic structure. 

 It could also be traced in places where there were no yolk 

 granules. 



Van Beneden, in 1883, recognised that in the ovum of Ascfma 

 the appearances of radiation arose throughout from radial ar- 

 rangements of the framework in certain places. Since he 

 regarded the supposed fibrillar reticular framework as the true 

 contractile substance, he therefore as good as stated that this 

 radiating arrangement of the otherwise irregular fibrilla? must 

 depend on their contractions, although he did not say so in so 

 many words. 



Leydig arrived at the same opinion as to the origin of 

 the sun-like figures by special arrangement of the framework 

 (1883, p. 144). In 1885 he particularly pointed out that he had 

 convinced himself of the correctness of this view by means of 

 his own investigations upon the eggs of Ascaris megalocephala. 

 Flemming, also, had in the meanwhile expressed himself to the 

 effect that the radiation was probably founded upon an " arrang- 

 ing and centring of the felt work of the cell substance." At the 

 same time he correctly criticised and refuted the opinion of 

 Anton Schneider referred to above. Finally, Carnoy (1884), 

 Frommann (1890), and other observers, came forward in support 

 of the view that derives the radiations from the radial arrange- 

 ment of the framework, so that it may now well be termed the 

 one which enjoys the most universal recognition. In addition 

 there is the fact that van Beneden, after renewed study of the 

 so-called systems of asters or rays, which he investigated in 

 company with Neyt, has come to the opinion that by contraction 

 of their moniliform fibrillae, which took origin from the proto- 

 plasmic trellis work (treillis), they mechanically caused both 

 nuclear and cell division. The structure of such a moniliform 

 fibril of the aster was supposed to be comparable to that of the 

 muscle fibrils, for which reason their contractility was rendered 

 probable. The so-called central corpuscles, which in van Beneden's 

 work were first proved to occur in the cell near the nucleus 

 even in the resting condition, only played in these processes the 

 part of supporting organs for the contractile fibrils of the aster, 

 among which were also reckoned the whole of the fibres of the 

 nuclear spindle, just as is usually done now, in spite of numerous 

 observations to the opposite effect, and indeed of contradictory 

 experiences of his own. At about the same time Boveri arrived 

 at a very similar conception of the part played by the fibrils of 

 the systems of rays in division in fact he even asserted that the 

 fibrils, or archoplasmic filaments as he termed them, could, by 



