ARCHOPLASM DURING MITOSIS IN LARVAL SALAMANDER. 193 



resembling the duplicated conical figure described by van 

 Beneden,^ and therein supporting the views advocated by 

 Watase.2 



This appearance is precisely what would be produced by the 

 evolution of halves of the spindle from a duplicated archo- 

 plasmic mass such as is represented in fig. 6, and I am 

 inclined to believe that it may have a most important bearing 

 on the curious " oblique division ^' described by Flemming.^ 



This subject, however, requires much further investigation. 



From the above description of the central bodies, and the 

 formation of the spindle, it appears that the latter structure is 

 formed entirely from the intervening archoplasm, and from 

 nothing else. 



The astral radiations, as Hermann has pointed out, are to 

 be regarded as the medium by which the chromatin fibres are 

 dragged along the central archoplasmic spindle on which they 

 slide. 



So far, the karyokinetic phenomena appertaining to the cells 

 constituting the embryonic genital ridge of the salamander are 

 only so many confirmations and extensions of those Platner 

 described as presented by the spermatocytes of Helix. From 

 this point onward, to that at which the daughter-nuclei begin 

 to collect about the poles of the di-astral figure, and an annulus 

 forms about the cell corresponding to the point of disruption 

 of many of the spindle-fibres to which I have alluded, the 

 metamorphosis is perfectly normal. Afterwards the spindle- 

 fibres show a strong and increasing tendency to become con- 

 centrated about the intermediate body of Flemming,* 



While the chromatin is gathering itself together, as in the 

 preceding diagram, fig. 24, the central bodies occupy the 



' " Nouvelles recherches sur la fecondation et la division mitosique chez 

 I'Ascaride Megalocephale," ' Bull. Acad. Belg.,' 3 ser., t. xiv, No. 8, 1887. 



" Loc. cit., p. 14; cf. also Wood's 'Hall Lectures,' 1891. 



5 ' Arcbiv fiir mikr. Anat.,' Bd. xxxvii, pp. 735 — 744. 



"• Op. cit. I have never seen more than one of these bodies in the cell of 

 the undifferentiated genital ridge of the salamander, and only one is figured 

 by Flemming iu the spermatocytes (fig. 14). 



