NOTES ON XEREOCYST1S 



85 



soon died. He also observed that the soral patches in which the 

 spores are produced disappear from the frond with the maturing of 

 the spores in them. This gives a very ragged appearance to the 

 older fertile fronds. Frequently young soral patches may be 

 found near the base of a frond, and mature ones in the middle 

 portion while large open spaces nearer the tip mark the places 

 where the older ones have disappeared. 



Fig. 2 Portion of two laminae of bladder kelp showing part of a soral patch in 

 each at the left, and two openings where the tissue has disappeared from the upper 

 one when the spores were mature. Photograph by S. M. Zeller. 



The duration of this plant has been discussed by Frye 4 and 

 Setchell. 5 The writer of this paper has frequently collected 

 specimens not exceeding 4 cm. in length during June, July and 

 August. Whether these were produced from spores of the same 

 season or from spores resting from the previous season he has no 

 means of knowing. Frye has found young plants up to 2.5 m. 

 long in March and up to 6 m. long in May, but evidence as to just 



4 Frye, T. C. Nereocystis luetkeana, Bot. Gaz., 42: 143. 1906. 



5 Setchell, W. A. Nereocystis and Pelagophycus. Bot. Gaz., 45: 125. 1908. 



