NO. 1 TAYLOR : PACIFIC MARINE ALGAE 59 



KEY TO GENERA 



1. Branches in many whorls covering the simple axis, at the tip with 

 a tuft of green branching filaments, below the ends of expanded 

 peripheral cells forming a regular surface which becomes calci- 

 fied, near the base denuded in old specimens .... Neomeris 



1. Branches in one, rarely to 3 whorls near the top of the axis, the 

 branches undivided, laterally coherent in each whorl to form a 

 generally calcified disk, but each bearing projections above and 

 often below near the base Acetabularia 



NEOMERIS D'Archiac, 1843 

 Neomeris Vanbosseae Howe 



Plants subcylindrical, usually curved, the apex rounded ; to 25 mm 

 tall, 3.5 mm diam. ; peripheral branches capitate, the ends about 150 ju. 

 diam. ; the upper calcareous cortex showing regular facets each penetrated 

 by a pore, this crust cracking off below, exposing the persistent calcified 

 subspherical sporangia which are laterally free, 145-205 fi diam.; lower 

 part of older plants denuded of sporangia, exposing calcified but laterally 

 free primary branches 25-30 fi diam., 500-600 fi long. 



Howe 1909, p. 80, pi. 1, figs. 4, 7, pi. 5, figs. 17-19. 



Mexico : Is. Revilla Gigedo, frequent in smooth pothole pools in the 

 littoral zone, Braithwaite Bay, I. Soccoro, no. 34-3j 3 Jan. 1934, and no. 

 JP-55, 18 Mar. 1939. 



ACETABULARIA Lamouroux, 1812 



Acetabularia parvula Solms Laubach, v. americana n. v.^^ 



Plate 1, Figs. 17, 18 



Plants small, 4-7 mm tall, the disks 2-4 mm diam., of 15-18 rays, the 

 rays moderately laterally adherent, broad, moderately thin walled, the 

 end rounded truncate, without evident apiculus; dorsal coronal projec- 

 tions radially slightly obovoid, 75-90 fx with generally 3, occasionally 4 or 

 5, hair bases. 



Solms Laubach 1895, p. 29, pi. 2, figs. 3, 5. 



■*9 Acetabularia parvula v. americana n. v. — Plantae 4-7 mm altitudine, discis 

 2-4 mm diam. constantibus, ex 15-18 radiis modice adhaerentibus partesque ex- 

 tremas rotundato-truncatas atque leves habentibus; projectionibus dorsalibus 

 coronariis obovatis, 75-90 n diam. radiali, 3-5 basibus pilorum munitis. Planta 

 typica in loco dicto Braithwaite Bay, I. Soccoro, Is. Revilla Gigedo, Mexico, legit 

 W. R. Taylor no. 34-16, 3 Jan. 1934. 



