42 J. T. CUNNINGHAM. 



cells from the epithelium of the mouth and branchiae of 

 the larva of Salamandra, Flamming, in his most recent 

 researches, was able to count the number of chromatic 

 loops present. The number in each case was twenty- 

 four, and in other cases, where the number could not be 

 determined, twenty-four was the probable total. He has 

 also seen under Seibert^s oil immersion a highly refractive 

 particle at the poles of the achromatic spindle, towards 

 which the threads of the spindle converge. This body has 

 the same relations as the polar corpuscle which Fol has 

 described in egg cells. In some preparations the chromatic 

 loops were seen to lie each Avith its bend on one of the 

 achromatic threads (figs. 41, 42, and 43). 



Differences between Strasburger and Fiemming.— In the 

 figures of vegetable cells given by Strasburger, rods and 

 granules almost universally take the place of the regular 

 looped threads described by Flemming. He differs, also, in 

 many other points from Flemming, who devotes a great 

 part of his latest paper to the discussion of Strasburger^s 

 views. If Strasburger's observations are conclusive it fol- 

 lows that the karyokinesis of vegetable cells is a process 

 agreeing only in the most general features with that which 

 Flemming has seen in Salamandra, and that there is no 

 exact correspondence between the successive stages in the 

 two cases. The only stage where any close resemblance 

 exists is that of the equatorial plate, where the achromatic 

 spindle, with the disc of chromatic elements at its equator, 

 is obviously homologous with the corresponding stage 

 described by Flemming in Amphibia, and Fol and others in 

 segmenting .ova. (For a complete series of the successive 

 changes, according to Strasburger, see figs. 85 — 108, Taf. 3 

 and 4, ' Zellbildung u. Zelltheilung,' 1880, from Liliiim 

 martagon : and figs. 60 — ^.69, Taf. 8, from Iris pumilla.) The 

 resting nucleus is figured by Strasburger as consisting of 

 large round granules of chromatic substance irregularly dis- 

 tributed in a homogeneous unstained matrix. Out of these 

 granules is formed a structure having a distant resemblance 

 to a convolution which does not break up into regular loops, 

 and forms no mother star, either of three dimensions or of 

 flattened form, but by irregular changes assumes a spindle 

 form, which, in the embryo sac of Liliuni martagon, consists 

 of a continuous mass of chromatic substance at the equator, 

 with threads of different lengths and thicknesses passing 

 from it towards the poles. A division of the chromatin 

 takes place at the equator and the threads travel toward? 

 1 ' Archiv. Mik. Anat.,' Bd. 16, 



