400 ALLAX HAXCOCK PACIFIC EXPEDITIONS \'()L. 12 



PLATE 42 



Fig. 1. I.itliophylluiri Farlo'ivii. The besinninp; of the senescent 

 stages of the thallus. The chambers in the central area 

 (the upper two thirds of the figure) have become highly 

 subdivided and small. The free edges of the septa have 

 died and have been cut back noticeably by abrasion. 

 However, the horizontal basal thallus is, on part of the 

 periphery (the lower right-hand portion), still grow- 

 ing and producing young vertical plates. I. Santa Maria. 

 X 0.95. 



