308 



MICROSCOPIC FORMS OF VEGETABLE LIFE. 



second is the condition of the genus Palmella; of which one spe- 

 cies, the P. cruenta, usually known under the name of " gory 

 dew," is common on damp walls and shady places, sometimes 

 extending itself over a considerable area as a tough gelatinous 

 mass, of the color and general appearance of coagulated blood. 

 A characteristic illustration of it is also afforded by the Hcemato- 

 coccus sanguineus (Fig. 103), which chiefly differs from Palmella 



in the partial persist- 

 Fio- 103. ence of the walls of the 



parent cells, so that the 

 whole mass is subdi- 

 vided by partitions, 

 which enclose a larger 

 or smaller number of 

 cells originating in the 

 subdivision of their 

 contents. Besides in- 

 creasing in the ordi- 

 nary mode of binary 

 multiplication, the Pal- 

 mella cells seem occa- 

 sionally to rupture and 

 diftuse their granular 

 contents through the 

 gelatinous stratum, 



H^tococous sanguineus my^no^s stages of development:- ^^^^ ^|^^^g ^ • j • 



T, Single cells, enclosed in their mucous envelope ; o, c, clusters & o 



formed by subdivision of parent cell ; d, more numerous cluster. tO a WnOlC CluStcr Et 

 its component cells in various stagesof division ; e, large mass of QTi(>g aS SCCU at 6 after 

 young cells, formed by the continuance of the same process, and , ' p ' j.r 



enclosed within a common mucous envelope. LUG manner 01 OHUcr 



simple Plants to be 

 presently described (§ 195), save that these minute segments of 

 the endochrome, having no power of spontaneous motion, can- 

 not be ranked as Zoospores. The gelatinous masses of the Pal- 

 mellese are frequently found to contain parasitic growths, formed 

 by the extension of other plants through their substance ; but 

 numerous branched filaments sometimes present themselves, 

 which, being traceable into absolute continuity with the cells, 

 must be considered as properly appertaining to them. Some- 

 times these filaments radiate in various directions from a single 

 central cell, and must at first be considered as mere extensions 

 of this; their extremities dilate, however, into new cells; and, 

 when these are fully formed, the tubular connections close up, 

 and the cells become detached from each other.' This is ob- 

 viously an additional mode of increase hj gemmation; analogous 

 to that which we shall meet with among the Confervacece (§ 198). 



' Although the Authors of the " Micrograph ic Dictionary" throw doubt upon this fact, 

 yet the writer, liaving Ijad the opportunity of verifying the observations of that most 

 accurate Algologist, Mr. Thwaites, can entertain no doubt of their correctness. (See 

 '■Ann. of Nat. Hist." N. S. toI. ii, p. .31.1,) 



