358 



Conjugate 



name of ' pore-organs ' and he considered them to be directly concerned in 

 mucus-formation, a view which is probably correct since there is no doubt 

 that mucus is passed outwards through the fine pores. The contents of the 

 pore-canal often terminate on the inner surface of the cell-wall in a button- 

 shaped or lens-shaped swelling, and from the outer end of the pore-canal 

 there often extends a delicate flower-like or club-shaped mass of tough mucus 

 through which the canal passes (fig. 226 /). In many cases this projecting 



Fig. 222. Various species of Staurastrum. A, St. BurkiUii W. & G. S. West, x468; B, St. 

 victoriense G. S. West, x450; C, St. unguiferum Turn. var. inerme (Turn.) W. & G. S. 

 West, x 468. a, front view of cell ; b, end or vertical view. 



mucous process is bifurcated (consult fig. 228 D and E 1 } and it is frequently 

 sufficiently resistant to reagents to stand out clearly after fixation. It may 

 also be yellow or even yellow -brown in colour, presumably owing to the 

 deposition of iron salts, and may therefore be more or less permanent in 

 character. More often this mucous process is entirely wanting or is replaced 

 by a small perforated button (fig. 226 H ). In most of the larger Desmids 



1 Consult also W. & G. S. West ('04 '11), t. 113, f. 15 ; t. 117, f. 5. 



