130 ERYTHEA. 



ment. Further information was given by the writer in his 

 " Kelp Notes " in this journal for March of the current year. 

 It is designed in the present paper to amplify and supplement 

 these notes and present figures of the adult plant and of young 

 plants of different ages, since no figures of this species have 

 ever been published and specimens are all but unknown in 

 herbaria. 



Distribution. 



Eisenia arhorea is limited to the coast of California and 

 flourishes best upon, or is perhaps even confined to, that part 

 of the Californian coast lying to the south of Point Concep- 

 tion. Dr. Eisen's original specimens were collected at the 

 Island of Santa Catalina, where the plant is found growing 

 attached, but are credited by Areschoug to San Francisco. 

 The importance of geographical distinction between the 

 different parts of the coast of California, and the citation of 

 very definite localities is becoming more and more necessary 

 as our alga3 are being studied more carefully, and it seems 

 probable that we shall be able, when considerable more defi- 

 nite information has been accumulated to recognize definite 

 northern or southern limits, as the case may be, for many of 

 our species, limits having very definite relations with the 

 position of the isotheral or isocrymal lines. 



Eisenia arhorea is abundant about San Diego where it has 

 been collected by Mr. Daniel Cleveland and by Professor Carl 

 Eigenmann. Professor Farlow has collected an abundance of 

 fine large specimens at San Diego also. At San Pedro and 

 Redondo, the writer collected plentiful material and a set has 

 been prepared for distribution. Dr. Anderson informs me 

 that he finds it occasionally floating in the Bay of Monterey, 

 but always after severe winds from the south and in the form 

 of more or less battered specimens. 



Adult 3IorphoIogy. 



A. Holdfast. 

 The holdfast of Eisenia arhorea, as is the case in most 

 Algse, varies very considerably according to the particular 



