115 



in dividing the spore into four cells. Here the similarity ceases. 

 The difference in the vegetative form, however, is too great to 

 •admit of its being closely related to the last named group. 



Another genus, Scaphospora speciosa, Kjellm., is described, 

 resembling Haplospora in external appearance, but is not so easy 

 to cultivate and is found in much smaller quantities; it differs 

 from it by having two kinds of reproductive organs, which are 

 called oosporangia and zoosporangia. The former are very simi- 

 lar to the intercalated sporangia of Haplospora] the contents at 

 first resemble those of the other vegetative cells, various changes 

 take place somewhat similar to those described \n Haplospora] 

 the nucleus, however, does not divide, neither is there a new 

 wall formed around the contents before they escape from the 

 sporangium case. The wall of this case dissolves at a conveni- 

 ent place, the contents escape, assuming at once a spherical 

 shape. Although the author was unable to trace the very next 

 steps in the development of this sphere, owing to the scarcity 

 of material and the difficulty of Its cultivation, he says these two 

 points of difference between it and the spore of Haplospora, viz : 

 there being only one nucleus and its lacking a membrane, are 

 sufficient to warrant its being considered an egg. The next stage 

 observed was that in which this egg was invested with a mem- 

 brane and had divided Into four cells, each containing a nucleus. 

 Some were found, having sent out rhizoid-like protuberances. 



The second kind of reproductive organ occurs on the same 

 individual. It consists either of a metamorphosed branch or 

 parts of branches easily distinguished by the large number of 

 little cells of which they consist. 



The direct escape of the contents of these zoosporangia w^as 

 not observed, but a large number of empty cases were found, 

 also some whose contents had only partially escaped. In these 

 the remaning spores appeared to be naked spheres with two small 

 chromatophores. No cilia could be distinguished. Now in the 

 fresh material containing the empty sporangium cases were 

 found numberless little swarm spores in active motion, whose 

 size and appearance corresponded to the spores found inside the 

 sporangia. These swarm spores, were long, egg shaped, with two 

 cilia, and the view that they were the developed spores of the 



