Chapter III 



Carotinoids in the Cryptogams 



The non-flowering forms of plant life, the chromolipoids of which 

 are considered in the present chapter, are as abundantly characterized 

 by pigments as the phanerogamous, or flowering forms. Indeed, 

 among the algae, which will be first considered, the more important 

 classes derive their names, at least their common designations, from 

 their general distinguishing color. The same is true in a few cases 

 for fungi, for example, the rusts. 



The information available regarding the character and distribution 

 of carotinoids among the lower forms of plants is, on the whole, more 

 abundant than might be supposed. Speaking first for the algae, it is 

 surprising to find that our knowledge is practically complete for cer- 

 tain of the classes, particularly the red and brown sea-weeds. On 

 the other hand, fragmentary information only is available for other 

 classes of algae, so that the subject of the carotinoids among the 

 algae is by no means as yet a dosed book. Some of the algae seem 

 to owe their characteristic color, at least in part, to carotinoids. This 

 is true of the brown sea-weeds as a class in the living condition. Cer- 

 tain species among other classes apparently owe their color entirely 

 to carotinoid pigments, for example, the so-called blood algae Haemo- 

 tococcus pluvialis, one of the Chlorophyceae, but this phenomenon 

 does not seem to be the general rule. 



Carotinoid-like colors are more common among the fungi than 

 among the algae, but the colors in many cases appear to be due to 

 other pigments. In general, it may probably be stated with some 

 degree of assurance that carotinoids are not so common among the 

 fungi as among the algae. In fact, many fungi appear to be entirely 

 devoid of carotinoid pigment, while practically all classes of algae 

 appear to contain pigments of this type to some extent, or at least 

 to give reactions w r hich may be thus interpreted. 



The study of the carotinoids which appear to be regularly pro- 

 duced by bacteria of certain species is practically an unexplored field. 

 Practically nothing is known regarding the character and distribution 



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