and on a new Sjjecies of Protococcus. 425 



to ten baby groups around them, while the phenomena of 

 enlargement, approach towards a globular form, and atrophy 

 of the spines have just now (October 19th) been most satisfac- 

 torily seen in one group of eight and in three groups of sixteen 

 cells each. (These specimens were taken from another gum- 

 bottle, in which a little of the sediment of the original one 

 had been placed about two months since, together with some 

 small bits of the jelly of Oplirydium versatile^ and where 80- 

 rastrum^ thus transferred, has multiplied as much as in its 

 original bottle, with even more robust dimensions.) 



The sediment of the original gum-bottle now became charged 

 with the old (fig. 1) and the new (fig. 8) groups of Sorastrum^ 

 so that from six to ten old and young might be counted in 

 each di'op of the sediment when placed on the slide for exami- 

 nation. 



4. To those who had observed the contents of any algal 

 cells (especially those of the so-called unicellular Algaj), re- 

 spectively divided up into microgonidia and macrogonidia, 

 and the former swarming round and passing into the latter 

 for impregnation, as in Cryptoglena lenticidaris^ Cart. (Annals, 

 ser. 3. vol. ii. pi. 8. figs. 18-27), it would not be unlikely that, 

 on witnessing a similar elimination in Sorastrum spimdosum^ 

 this should also be set down as the time for impregnation and 

 formation of the spore. Hence I was not surprised to see for 

 the first time (viz. on the 6th of September) a spherical spo- 

 rangium, 13-6000tlis inch in diam., densely filled with gonimic 

 contents presenting a deep dark sea-green colour, precisely 

 like that of the groups of Sorastrurn, and totally different from 

 that of everything else in the gum-bottle (fig. 9). 



Moreover, on minutely examining this sporangium, it was 

 observed to be invested with a soft gelatinous transparent en- 

 velope (a a), and to possess a tough transparent coat {b), which, 

 when bm-st, was found to be filled with the usual contents 

 of a sporangium, viz. minute grains of starch, chlorophyll, oil- 

 globules, &c., but no distinguishable nucleus. 



Subsequently this sporangium became more abundant, and. 

 in some cases double, but always presented the same size and 

 other characteristics mentioned, with the exception that occa- 

 sionally it appeared to be a little elliptical. 



How and when this sporangium was produced, assuming it 

 to be that of Sorastrum, I can only conjecture from the resem- 

 blance of the baby groups eliminated in the third stage, cor- 

 responding to that which I had seen to be the moment of im- 

 pregnation in the unicellular Alga to which I have alluded, 

 where some of the groups eliminated were in the form of 

 microgonidia and others in that of macrogonidia, t. e. of minute 



