NO. 1 TAYLOR: PACIFIC MARINE ALGAE 305 



KEY TO SPECIES 



1. Main axes or long branches with some of the nodes regularly 

 without a branchlet or a branch rudiment, the apices strongly 

 upcurved, the diameter 75-150 fi; branchlets generally with 7-8 

 pericentral cells H. secunda 



1. Main axes or long branches with a branchlet or a branch rudi- 

 ment from each node; apices of the main branches slightly up- 

 curved; branchlets generally with 12-14 pericentral cells H. tenella 



Herposiphonia secunda (C. Agardh) Ambronn 



Howe 1920, p. 574; Taylor 1928, p. 176, pi. 25, figs. 8-10. 

 Panama: on the tips of the branches of Galaxaura in tide pools, I. 

 Jicarita, no. 34-505 B, 20 Feb. 1934. 



Herposiphonia tenella (C. Agardh) Ambronn 



Howe 1920, p. 573; Taylor 1928, p. 177, pi. 25, fig. 11. 



Mexico : Nayarit, rare as dredged on Bryothamnion from 6-9 meters' 

 depth at sta. 971 near I. Maria Magdalena, Las Tres Marias, no. 39- 

 665 (p. p.), 9 May 1939. 



BOSTRYCHIA Montagne, 1838192 

 Plants filiform, dull purplish, ordinarily regularly bilaterally branched, 

 the branches near the apex usually incurved; for the most part poly- 

 siphonous, the pericentral cells equaling the axial in length or divided 

 transversely; rhizoidal, stoloniferous and erect branches often differenti- 

 ated, the branchlets often monosiphonous at the tips; tetrahedral spo- 

 rangia whorled in special siliquose branchlets with several sporangia in 

 each segment ; pericarps subglobose, terminal on the branchlets. 



KEY TO SPECIES 

 1. Haptera consisting of transformed branchlets . . . B. radicans 



1. Haptera formed by outgrowths of the pericentral cells . . 2 



2. Cortication rhizoidal B. CalHptera 



2. Cortication parenchymatous 3 



3. Branchlets of the last order entirely monosiphonous . . B. tenella 

 3. Branchlets of the last order only monosiphonous for about 5-15 



segments near the tips ^- Binderi 



192 Determinations in the genus Bostrychia were made or confirmed by Dr. 

 C.-K. Tseng. 



