188 



BIOCHEMICAL SYSTEMATICS 



Leguminosae: Although the sub-families Mimosoideae and 

 Caesalpinioideae contain a few cyanogenetic 

 species, the character is best expressed in the 

 Papilionoideae wherein most tribes contain 

 cyanogenetic species. Trifolium repens contains 

 two different types of cyanogens, apparently 

 the only such example. 



An unusual cyanogen occurs in the legume genus Indigofera. 

 Morris et al. (1954) studying a toxic substance from the leaves of 

 Indigofera endecaphylla, found it to be ^-nitropropionic acid; 

 NO2 — CH2CH2COOH, the aglycone of hiptagin and karakin. Accord- 

 ing to these authors they isolated the compound from several species. 

 In a subsequent paper, Cooke (1955) studied several species of 

 Indigofera with the following results: 



Other workers (Schilling and Strong, 1955; Dupuy and Lees, 

 1956; Bell, 1962) have obtained yet another unusual nitrogenous 

 derivative from Lathyrus odoratus and Lathyrus pusillus. This sub- 

 stance, )S-N-(Y-L-glutamyl)-aminopropionitrile, is one of the agents 

 producing the condition known as lathyrism (Selye, 1957), in 



