712 MINNESOTA BOTANICAL STUDIES. 



The author expresses his deepest thanks to Professor Conway 

 MacMillan and Miss J. E. Tilden, who cared for him very 

 kindly in every way during his stay at their private station ; and 

 to Professor J. Matsumura, of Tokyo, who offered many valu- 

 able suggestions on this work. 



SYNOPTICAL KEY OF CORALLINE ENUMERATED IN THE 

 PRESENT PAPER. 



A. Conceptacles wart-like protuberances, on a surface of an articulus. 



o. Branches not pinnated. 



a. Articuli cylindrical Amphiroa cretacea L tasmanica . 



b. Articuli of the upper and the middle portions cylindri- 

 cal, subcompressed or compressed. 



Amphiroa tuberculosa. 



c. Articuli of the upper and middle portions approximate, 

 with depressed wings Cheilosporum californicum. 



00. Branches pinnated. 



a. With short and thick stipes; upper articuli of the 

 branches cordate or sagittate with round lobes; external 

 margins of the ultimate articuli thick. 



Cheilosporum frondescen <. 



b. With long and thin stipes ; upper articuli of the branches 

 sagittate with acute lobes ; external margins of the ulti- 

 mate articuli thin Cheilosporum planiusculum. 



c. With long and thick stipes ; articuli of the axial branches 

 hexagonal, without evident rib ; conceptacles sometimes 

 stalked Cheilosporum MacMillani 



B. Conceptacles stalked, taking place of segments. 



o. Branches regularly pinnated, flabellate. 



Corallina ojficinalis var. chilensis. 



oo. Branches irregularly pinnated, several pinnules around the 

 top of an articulus. 



a. Pinnules not confusedly ramous. 



Corallina vancouveriensis. 



b. Pinnules confusedly ramous and prickly. 



Corallina aculeata. 



HABITAT OF CORALLINE AT PORT RENFREW. 



The coast near the Minnesota Seaside Station chiefly consists 

 of sandstone beds spreading horizontally. The beds are cov- 

 ered with water at high tide, and drained at low tide, leaving 

 a good number of pools. The Corallinae are mostly found 



