WIXGE, CYTOLOG. STUDIES IX THE PLASMODIOPHORACE.E. 29 



three times in succession. Chromosomes (2—5) are present 

 and distinct karyokinetical spindles. Thus arise first 2, then 

 4 and finally 8 walless spores which are zoospores. Juel ob- 

 served these zoospores swarming while ahve. They were 

 pyriformed and provided with 2 lateral cilia. 



Sorolpidiiim Betae Nemec. 



NÉMEC has given a preliminary^ and subsequently a 

 more detailed description-^^ of a new type found by him and 

 designated Sorolpidium Betae n. gen. et n. sp. Nemec is 

 evidently unacquainted with Juel's above mentioned Pyrrho- 

 sorus as in that case he would undoubtedly have pointed out 

 the great similarity between the two. In reality the two 

 forms are exactly alike as regards development except in 

 this, that NÉMEC states that the »Sorosporangien» in his 

 Sorolpidium divide into 2 — 4 parts at the formation of the 

 zoospores while Pyrrhosorus forms 8 zoospores with one lateral 

 cilia. During the vegetative amoeba-stage he has seen the 

 peculiar Plasmodiophoracea-nuclei divide in the w^ell-known 

 characteristic way. — Xemec, however, propounds some prob- 

 ably untenable theories about the homology between the 

 organs of the Plasmodiophoraceae and those of his Sorol- 

 pidium. 



He expresses himself in this way: 



»Würde man nur die nackten vegetativen Körper sowie 

 die Sorosporangien von Sorolpidium kennen, so könnte man 

 den Organismus ohne weiteres zu den Plasmodiophorazeen 

 zählen.» I find this assertion somewhat daring; it must 

 namely be remembered, that none of the »plasmodia» in the 

 species, which up till now have been classed under Plasmo- 

 diophoraceae are enclosed by a membrane. — »Aber der Um- 

 stand, dass in jedem Sorosporangium — ähnlich wie bei 

 Rhizomyxa — mehrere Schwärmsporen entstehen können, 

 spricht gegen die Auffassung, dass hier einfache Sporen vor- 

 liegen. Da schon bei Rhizomyxa und wahrscheinlich auch bei 

 Sorolpidium zuweilen nur ein Schwärmer in dem Sorosporan- 

 gium entsteht, könnte man annehmen, dass dies bei Plasmo- 

 diaphora Regel geworden ist, so dass die Sorosporangien 

 monospor geworden sind und daher scheinbar einfache Sporen 

 vorstellen.» 



