NO. 10 DAWSON : MARINE ALGAE, GULF OF CALIFORNIA 319 



Geramium paniculatum Okam. 



Okamura, Icones Jap. Algae IV, p. 114, pi. 179, figs. 8-16. 



D. & R. 3408 from Guaymas, December, though sterile, is not dis- 

 tinct in any particular from Ceramiiim paniculatum hitherto known only 

 from Japan. The occurrence of sharp, 2-3-celled points which form on 

 the convex sides of the forcipate branches and persist in older parts is an 

 outstanding character and marks this species as unique in the Gulf. 



Geramium gracillimum Griff. & Harv. 



Griff. & Harv. in Harvey, 1846-1851, pi. 206. Ceramium byssoideum 



Taylor, 1928, p. 190, pi. 27, figs. 20, 21. Ceramium transversale 



Collins & Hervey, 1917, p. 145; Setch. & Gard., 1930, p. 170, 



pi. 7, figs. 23, 24. 



Taylor has recognized Ceramium transversale as a small form of C. 



byssoideum; Feldmann-Mazoyer places C. byssoideum as a variety of C. 



gracillimum (1940) ; B0rgesen, 1934, places both C. byssoideum and C. 



transversale under C. gracillimum. Since our material from the Gulf 



corresponds well with topotype examples of C. transversale as well as 



European material, it seems best to place it under this name. Certain 



differences are apparent, however, between our material and that of 



other parts of the world, and distinctive characters perhaps will be found 



when more ample material is available for minute study. 



D. 169a, Turner's Island, Jan.; H. 614c, 615, dredged in 40 meters, 

 San Jose del Cabo, Aug. 



Geramium Gamouii sp. nov. 

 Plate 51, Figs. 2, 3 



Frondes 3-4 mm. altae, laxe dichotomae, ramis secondariis per occasionem, 30- 

 40 n diam., tantum nodis corticatae, apicibus non forcipatis; zonis corticatis a 

 internodiis 100-150 |li longis separatis; tetrasporangiis verticilatis, nudis et curte 

 pedicellatis, involucris apertis, hemisphericis, corticalibus, plerumque 125 \k latis 

 circumdatis. 



Fronds 3-4 mm. high, sparingly dichotomously branched, with occa- 

 sional secondary lateral branches, 30-40 fx diam., corticated only at the 

 nodes ; apices not forcipate, with a conspicuous terminal cell which after 

 the first division cuts off cells immediately in several planes, with many 

 slender, early deciduous hairs; cortical zones separating early, only 



