22 THE HANCOCK PACIFIC EXPEDITIONS VOL. 3 



OSCILLATORIACEAE 

 Schizothrix Hancockii^ sp. nov. 



Stratum expansum, pulvinatum, subaeriale, carneo-durum, non 

 calce impregnatum, ad tria centimetra altum, externe luteo-olivascens 

 vel luteo-aerugineum, interne griseo- ad luteoli-aerugineum, super- 

 ficie planum; filamentis internis tortuosis, praecipuius dense intricatis, 

 parce pseudoramosis, vulgo S/x ad 7/i, crassis, superne caespitosis, 

 saepe parallelis, plus minusve tortuosis; vaginis cylindraceis, tenuibus, 

 firmis aut ad superficiem pulvini plus minusve diffluentibus et cras- 

 sioribus, hyallnis, non lamellosis, chlorozincico iodurato caerules- 

 centibus; trichomatibus dilute aerugineis, intra vaginam singulis aut 

 rarissime binis, 3/i ad 4/a crassis, ad genicula pauUo constrictis; 

 articulis diametro trichomatis 1- ad 2-plo longioribus, 3fx. ad Sfi longis; 

 dissepimentis baud conspicuis, non granulatis; protoplasmate homo- 

 geneo aut subtiliter granuloso; cellula apicali rotundata; calyptra 

 nulla (v. in form.). Fig. 75. 



Hab.: ad lapides planes littorales, MEXICO: Revilla Gigedo 

 Islands, Braithwaite Bay, Socorro Id., No. 4, January 2-4. (Type 

 in the U. S. National Herbarium). 



This alga is placed in the section Hypeothrix near H. cyanea 

 Nageli (in Kiitzing, Species Algarum, p. 269. 1849), to which it 

 appears to be most closely allied. Unfortunately H. cyanea is an 

 ill-described form for which we are not at present certain of the 

 original specimens or the type locality. According to Professor 

 Taylor's notes, our alga was found in great abundance on 'smooth 

 littoral rocks,' forming rounded or extended cushions often several 

 centimeters in breadth. These cushions were 'firm-fleshy, nearly as 

 tough as a Laminaria stipe,' the 'surface soft but particularly 

 smooth.' The toughness of the mass appears to be due to the fact 

 that the filaments in the interior are very compactly intertwined. 

 On the surface the filaments are somewhat less tortuous, often 

 parallel, and always either caespitose or repent, never forming 

 symplocoid fascicles. False branching is more common than can be 

 demonstrated with facility because the filaments are so contorted 

 that the branching is as a rule obscured by the presence of other 

 filaments. The sheaths are thin and well-defined, especially in the 



•* Named in honor of Captain G. Allan Hancock, through whose generosity this 

 expedition was made possible. 



