MacDougal : Symbiosis and Saprophytism 521 



The v'ariation in the leaf is also accompanied by increase in the 

 length of the offsets, the decrease of the capacity of the storage 

 organs, and the diminution in the number of the roots. The coral- 

 loid offsets of Calypso have not been seen to give rise to new plants 

 as in Aplcctniiii. 



The very great divergence of individuals from the type in leaf 

 and flower characters in this species has been a subject of remark 

 among systematists for many years, and Mr. Heller has recently 

 raised one of the most pronounced forms to specific rank (4). 

 Whether such variations of the shoot are directly correlated witii 

 the development of the mycorhizal structures or not can not be 

 definitely stated. The matter may be determined only by the 

 careful examination of specimens in the field throughout the habitat 

 of the species. 



Corallokhiza Arizonica Wats. 



(No. 94 of collection of 1898 by MacDougal.) 



The general morphology, and occurrence of the fungus of the 

 coralloid branches of Corallorhi::a have been somewhat fully de- 

 scribed by Schacht, Irmisch, Reinke and others, chief attention 

 having been paid to Corallorldza Corallorliiza{\^^ Karst (C innatd). 

 The results at hand, however, were obtained quite early in the 

 history of investigation upon this subject, and certain details now 

 known to be of great interest were not touched upon in these 

 earlier researches. It was deemed advisable, therefore, to make a 

 reexamination of the mycorhizal structures of another representa- 

 tive of the genus, with especial attention to the physiological rela- 

 tions of the members of the symbiotic union. Jennings and 

 Hanna (6) have recently published a short paper on C. innata in 

 which it is stated that the symbiotic fungus is a " hymenomycete 

 and commonly an argaric." Clitocybc iiifundibiiliformis Sch., was 

 found attached to the coralloid formations in one instance, and 

 '' Hystcraiigiuin stoloiiifenivi of Tu/asne" in another in a manner 

 indicative of the identity of these species with the symbiotic fungus. 



CorallorJiiza Arizonica is a native of the upper part of the tran- 

 sition zone and the Canadian zone in the Rocky Mountains. The 

 subterranean portion of the plant consists of a dense mass of coral- 

 loid stems which lie as deep as 20 cm. below the surface, and from 



