152 ge:neeal history of the ineusokia. 



appears, and the cilia too, when this species passes into the ' still ' form. 

 Here it undergoes the same kind of division that it does in the active state ; 

 but the parent-cell, instead of becoming distended by imbibition, remains 

 closely attached to the daughter- cells, so as to give the group a mulberry 

 shape. How long it remains in the ' still ' form I am ignorant ; but 

 having only seen it in the active state during the months of May, June, and 

 August, and throughout the rest of the year in the ' still ' one, I am in- 

 clined to think that it only comes into the active state during the summer 

 months, and then for the purpose of fecimdation. 



" In several instances, also, where I have found this Chlamydococcus with 

 Eudorina, they have been accompanied by long Closteriform cells. It was 

 the case in that above mentioned, where the latter was imdergoing impreg- 

 nation. Some of these have an eye-spot, which, with the natui'e, arrange- 

 ment, and general aspect of theii* internal contents, shows that they belong 

 to the class of organisms with which they are associated. Theii' cell-wall 

 also is more or less plastic, or was so when they were assuming this spicular 

 form ; for many have one or more diverticula extending from them, some are 

 bifid, and a few irregularly stellate. AMiat they are, I know not ; but Dr. 

 Cohn has figured the same kind of cells, in company with Splicei-o_pha annu- 

 lina, under impregnation." 



Mr. Currey {op. cit. p. 216) has noticed and figured what he conceives to be 

 a generative variety of Chlamydococcus (XX. 24). " This," he says, " I take 

 to be a state of Chlamydococcus. The outer membrane was colourless, and 

 the two internal globular cells of a clear, bright ruby crimson. The pecu- 

 liarity of the plant consisted in the fact of the cell being filled with minute 

 staff"- like subcylindrical bodies in active motion, precisely similar to the 

 spermatozoa of Vaucheria. I watched these bodies at inten^als for about 

 twenty-four hours ; and the motion was incessant. At the end of that time 

 the cell slipped amongst some other AlgsG on the same shde and was lost. 

 Whether these little active organisms wxre reaUy spermatozoa, or whether 

 they belonged to the mysterious bodies w^hich, in some way or another, are 

 supposed to find their Avay from without into the cells of Algae, it is im- 

 possible to say." 



The next figm-e (XX. 25) is also copied from Mr. Currey, and, as he re- 

 marks, evidently " represents the final stage of some Yolvocineceva. which the 

 gonidia have become encysted." We allude to it here, although it does not 

 belong to Chlamydococcus. Mr. Currey observes further, " I notice it be- 

 cause the encysted cells were of a pale yeUowish-brown colour, and covered 

 with minute pits or depressions, and were altogether different from those of 

 any other Alga with which I am acquainted. In Pandorina and Stephano- 

 Sjphcera the resting- spores are red, in Volvox bright orange; and in neither 

 case are there any such marldngs as those in the membrane of the cells 

 showTi in the figure referred to." 



GoNiUM (XIX. 32-37). — This genus received considerable attention from 

 MuUer and Ehrenberg. The latter described it as composed of sixteen 

 Monads, resembling Chlamydomonas in all points except in the absence of 

 an ej^e-speck, collected together in a quadrangular tablet, with fi'om three to 

 six intercommimicating tubes or cords. Each Monad was said to be enclosed 

 in a hyaline lorica, called here a mantle (lacenia), which it could at times 

 quit ; also to have two filaments (proboscides) extended from the mouth, re- 

 presented by a clear spot at their base ; several clear stomach- sacs, a con- 

 tractile vesicle, two round sexual glands, and numerous green ova. Detached 

 individuals, he added, swam like Monads, in the direction of the longitu- 

 dinal axis of their bodies, with tlic mouth in advance ; but when in tablet- 



