PLATE XXIV. 



Figures magnified 500 diameters. 





Fip. 1 



ATTHRor>F-Mr< Incus, large form, 



" ' smaller form, 



P\GF. 



. 07 



26. 



>- 



29. 



" 33. 



97 



long spined variety, . . '.'7 



" " depress '1 \ ariety, ... 07 



" " quadrate variety, . . .97 



quadrate variety, -mailer, . . 97 



crenate-cuneate, . . .97 



mm' cells conjugating, . . 97 



z\ gospore < l.-\*l [ *< I. . . .97 



end view of cell. . . . 97 



ArTHRODESMUS SUBULATl 8, front and end view, . 9r> 



^rthrodesmus ovalis, front and end view, . . 96 



^rthrodesmus oRBicuXARis, front and end view, . 96 



ARTHRODESMI S Ql IDRIDENS, fronl and end view, . . 96 



\. i : 1 1 1 1 : < > i i - m i - OCTOCORNfS, Var. twin spined, . . 97 



larger and smaller typical form, 97 

 ' 08MA i:ii M 3UBORBK I I \ I: I .. . . .78 



I > i ~ m 1 1 > 1 1 " m i yi.im'Kk i m. Compare Plate III, tig. 1, i<> illus- 



trate the I i \ isi< >n "I a .ill in the 

 l*i* icetw i 't u n <\\ tli. . '_'"> 



ElYAiiOTHKi \ in ii ii \- Compare Plate I. fig 1. the middle 



ell i- normal, tin other two enlarging 

 preparatory to division in the proc< 

 of growth, . . '_'"J 



Cosmarii m Botrytis, i w <> eel lb, opening "n one side, putting 



forth i\ tioplasm, uniting, thus perform- 

 ing the first act of conjugation. . 74 

 rhe whole contents, cytioplasm, >>! tin- cells, poured out, com- 

 mingled and formed into the c\ gos.pore, .... 19 

 Tin' tubercles on the membrane formed around (In- mass of cytio- 

 plasm (fig. 28, developed into spines. In the process of further 

 development, tin- membrane breaks, let> oul some "i the cytio- 

 plasm; (fig. 29, tin- assumes a spherical form, fig. 30,) mem- 

 brane increases in thickness and numl>er of layers; the contents 

 divide in i. in- direction. I'm:. .".I. then subdivide in a transverse 

 direction, fig. 32). Two or four daughter cells are thus formed 

 in all respects like tin- mother cell, except in the granules of the 

 membrane; these develop later, . . . . .19 

 W'vm containing a number ol -mall Closteriums; supposed to 

 he the development of a zygospore b\ another process, . . 19 



