CAROTIXOIDS IN THE CRYPTOGAMS 103 



of certain species, e.g., II<i< matocoCCUS, in the resting stage are diarac- 

 teri/.ed by a deep red or violet pigmentation. The species which have 

 been examined tor carotinoids represent all the important orders. 

 These are given in Table 10. 



The development of the question of the character of the pigments 

 other than chlorophyll which characterize the green alga- has followed 

 closely the development of the ideas regarding the carotinoids in the 

 higher plants, as given in Chapter II. For example, the earliest 

 workers, i.e., Colin (1850), DeBary (1856), Caspary (1858), Hilde- 

 brand (1861) and Frank (1877) observed merely that the yellow or 

 red pigments present in the algae which they examined responded to 

 extraction by the fat solvents and gave either the blue color reaction 

 with concentrated H 2 S0 4 , characteristic of the pigments later known 

 as lipochromes, or the blue color with iodine which also characterizes 

 these pigments. The spectroscopic studies of Nebelung (1878) unfor- 

 tunately contributed very little to the elucidation of the character of 

 the pigments present. Klebs (1881) made a more thorough study 

 of the properties of the "yellow oil" in certain species, and mentions 

 properties now well recognized as class characteristics of the 

 carotinoids. 



Borodin (1883) appears to have first definitely recognized the rela- 

 tion of the yellow pigments of the Chlorophyceae to those of higher 

 plants and isolated red rhombic carotin crystals from Spirogyra. 

 Molisch (1896), Tammes (1900) and Kohl (1902) as well as van 

 Wisselingh (1915) have also demonstrated the presence of carotinoids 

 in a number of species using the Molisch micro-crystallization test. 



Rostafinski (1881) first expressed the possibility of xanthin (older 

 terminology for carotin) being present in the species of green 

 algae which he examined. Willstatter and Page have not only shown 

 that this is the case for Viva lactuca but have determined both carotin 

 and xanthophyll quantitatively in this species. The amounts found 

 were 0.0243 grams of carotin and 0.0643 grams of xanthophyll per 

 kilo of fresh material. The interesting point here is that practically 

 the same proportion between carotin and xanthophyll is found to 

 exist in this species of algae as in the leaves of the flowering plants. 



Attention has already been called to the interesting phenomenon 

 of the red color of certain species of Chlorophyceae in the resting 

 stage. Special study of the character of the pigments present in 

 Sphaerella (Haematoco^cus -- Chlamydococcus) pluvialis, the so- 



