APPENDIX D. Ixxxiii 



midiatus. In the quadripartite Zoospores, with the secondary 

 cells arranged in one plane, we have a Gonium (Fig. 37). 

 That with eight segments (Fig. 38) corresponds to Pandor- 

 nia Morum, and that with sixteen to Botryocystis Volvox 

 (Fig. 44). When the Zoospore is divided into thirty-two 

 segments, it is a Uvella or Syncrypia (Fig. 40). When 

 this form enters the " still " stage, it may be regarded as a 

 form analogous to Microhalola protogenita ; this Algal genus 

 is probably, speaking generally, only the product of the 

 Uvella division in the EuglencB or other green forms. The 

 naked Zoospores (Fig. 32), finally, would represent the form 

 of a Monad, or of an Astasia ; the caudate variety ap- 

 proaches that of a Bodo. ... A critical and comparative 

 consideration of the foregoing facts would therefore appear 

 to render untenable almost all the principles which" modern 

 systematists have hitherto adopted as the basis for the 

 construction of their Natural Kingdoms, Families, Genera, 

 and Species.' 



According to Itzigsohn ^, Phytozoa intervene as stages in 

 the developmental history of the Oscillalorice. The trans- 

 formations recorded in these observations are of a most re- 

 markable character. The filaments of Oscillatoria tenuis are 

 said to break up into distinct fragments which soon assume 

 a spherical shape. These bodies (gonidia) gradually increase 

 in size, become motile, and present in all respects the aspect 

 of individuals belonging to the genus Chlamydojiionas. After 

 these have attained a certain size, a red eye-point becomes 

 visible in them, and after passing through a great many inter- 

 mediate forms they develop into perfect EuglejicB. These in 

 their turn become encysted, and subsequently by a minute 

 self-division of their contents they are resolved into motile 

 ' microgonidia' which are soon liberated, and then swim about 



^ ' Journ. of Microsc. Science,' 1854, p. 189. 



/2 



