76 



BIOCHEMICAL SYSTEMATICS 



Table 5-1. Results of titrating, with the photronreflectometer, antisera against 

 four species of Magnolia with antigens from several species of the genus (Johnson, 

 1953). By permission of the Serological Museum. 



group is supported by the data, while Liriodendron is relatively 

 distant, serologically, and Illicium, which has been removed from 

 the Magnoliaceae by some investigators on anatomical grounds, 

 gave no reaction. Illicium was shown to produce a highly reactive 

 antiserum, when tested against homologous serum, so that the lack 

 of reaction with Magnolia virginiana antiserum is not due to generally 

 low antigen content. It is notable that McLaughlin (1933) placed the 

 genus in the Hamamelidaceae. However, Disanthus, in this latter 

 family, gave no reaction with Illicium, perhaps supporting its treat- 

 ment by some taxonomic workers as a monotypic family, Illiciaceae. 

 At the species level the data suggest a closer serological re- 

 lationship between the Asiatic species. Magnolia obovata and the 

 American species, M. tripetala than between the latter and two other 

 American species, M. acuminata and M. virginiana. Magnolia por- 

 toricensis (Table 5.1) is farthest removed from all species, and, accord- 

 ing to Johnson, there is some morphological evidence to support its 

 separation as a single species of a separate sub-genus. 



