Howe: Phycological studies 507 



whose tragic and much lamented death in connection with the 

 recent civil disturbances in Mexico occurred on April 29, 191 1, a 

 few days after he had communicated this and other Lower Cali- 

 fornian alga.- to the writer for determination. 



Fauchea (?) mollis sp. nov. 



Thallus thin (25-35/*) and membranaceous when dry, soft, 

 lubricous, and 165-350/* thick when moist, cespitose-decumbent, 

 flabellately subdi-trichotomous, the mats 6-9 cm. in diameter, 

 the main segments mostly 5-8 times forked, radiating from a 

 center and more or less overlapping in 2-4 layers, the layers here 

 and there concrescent and coherent chiefly by deflexed more or 

 less specialized originally marginal lobes, axils rounded and the 

 segments again approximate or often overlapping; segments 

 short-oblong, subquadrate, or occasionally subcuneate, 2-15 mm. 

 broad, mostly as broad as long, margins entire, the terminal 

 segments 2-5 mm. broad, rounded-truncate or bi-trifid-retuse; 

 color a dull brownish red or greenish rose ; medullary layer of 2 (3) 

 series of large nearly empty cells, these mostly oval or elliptical 

 and 82-275/1 X 68-137/1 in cross section, rounded-hexagonal or 

 rounded-oblong when viewed through the cortex, without smaller 

 interstitial cells, passing abruptly to the thin subcortical layer 

 of 1-4 series of much smaller cells; cortical layer of mostly 2 

 series of minute cells 5-9/t high, anticlinal filaments scarcely 

 recognizable unless at margins, walls of cortical cells soft, gelat- 

 inous, confluent, and hardly visible when soaked out, other parts 

 wanting. [Plate 32; plate 33, figure 6.] 



La Paz, Vives 18a (type) and nf. 



The specimens described above are apparently sterile, but in 

 habit and vegetative structure they have so much in common 

 with Fauchea that we can feel little doubt as to their generic 

 affinities. Fauchea (?) mollis is perhaps most nearly allied to the 

 Australian F. nitophylloides* but the segments of the Baja Cali- 

 fornia plant are short-oblong or subquadrate instead of linear, 

 the thallus is much thicker (165-250/z vs. 65-85/1) and much more 

 gelatinous, so that it adheres very firmly to paper, the medullary 

 cells are much larger (82-2 75/c vs. 27-68/x, long diameter in cross 

 section) the walls of the cortical cells are gelatinous and con- 

 fluent when soaked out instead of firm and distinct, and the color 

 is a dull brownish red or greenish pink instead of scarlet. 



* For the privilege of examining authentic material of this species we are 

 indebted to Professor W. G. Farlow and Mr. F. S. Collins. 



