—73-- 



Contingent phases: (a) Laciniae deformed and deeply pitted, thalline 

 exciple rugose. (See Hasse, Contributions U. S. Nat. Herb. 17: io6. 1913.). 



(b) Laciniae stout, swollen (var. novo robusta). Type: U. S. Nat. Herb., 

 Agiabampo, Mexico, 1890. -leg. Ed. Palmer. Similis R. comheoidi Nyl.,, 

 thallus robustior, niger infra (altit. 1.5-2.5 centim., cras- 

 sit 3-4 millim.), minutae faveolae; apothecia terminalia 

 (latit. 5-7 millim.). Habitat in rupibus. Also seen from 

 Guadalupe Island. 



Substrata: On maritime rocks (sandstone, granite) 

 and, it is said, on shrubs and trees. 



Distribution: Common in the Transition Zone on 



the Pacific Coast from Marin County to San Diego, 



California. It has been recorded inland two miles at 



Pilarcitos Creek canon at an altitude of 250 feet. 3— Distribution 



Stations: California: Monterey; Point San Pedro; r „ t 



' 'of Ramahna com- 



Diego; Mission 



Catalina Island; San 



San Mateo Co. 

 Dolores. 



Observations: This generally saxicolous species, distinguished by its 

 more podetiiform growth and terminal, corymbose apothecia, was not 

 recognized by Tuckerman. It is often difficult to separate it from ceruchis, 

 with which it undoubtedly intergrades, and like testudinaria is of doubtful spe- 

 cific rank. There are even phases which approach homalea and others which 

 have been referred to hiimilis. The examples of this and the type are always 

 less rigid and typical if growing on wood; in fact the species seem to be largely 

 based on the results of substratal growth. 



ExsiccATi: No. i, Lich. Boreali-Amer., Cummings, etc. ^'San Mateo Co." 

 Cal., Feb. 17, 1893. M. A. Howe, called R. ceruchis. 



No. 91, Decades N. A. Lich., Cummings, etc. — data as above. 



No. 1369, Krypt. Exsic, Zahlbruckner, Pilarcitos Creek canon, Cal., 

 A. C. Herre. 



[To be co7itimied] 



Explanation of Plates V-VII 

 Plate V 



1. Transverse section of the thallus of Ramalina homalea showing the coalescent 

 hyphae of the medulla and the decomposed cortex of the cortical layer. 



2. The same of Ramalina ceruchis. 



3. Transverse section of an apothecia of Ramalina canaliculata showing exciple 



and the decomposed cortical layer. 



4. Transverse section of the thallus of Ramalina populina showing the decom- 



posed cortical layer and the arachnoid medulla and axis. 

 Enlarged 25 diam. — details 300 diameters. 



Plate VI 



Transverse sections of the thallus of the genus Ramalina showing the de- 

 composed cortical layer and the distribution of gonidia. 



