NO. 10 DAWSON : MARINE ALGAE, GULF OF CALIFORNIA 297 



Gracilaria veleroae sp. nov. 

 Plate 70, Fig. 2 (left) 



Frondes 6-8 cm. altae, complanatae, crasso-membranaceae, basi cuneatae e 

 disco parvo orientes, irregulariter dichotomo-flabellatae, segmentis plerumque 5-7 

 ram. latis, integris; internodiis curtis, 1-1.5 cm.; apicibus rotundatis; frondibus 

 300-400 Ji crassis; cellulis internis magnis, parietibus tenuibus; corticibus essen- 

 tialiter unistratosis cellulis forma laterium; cystocarpiis marginalibus, 1 mm. 

 diam., carpostomio leviter elevato. 



Fronds 6-8 cm. high, complanate, thick-membranous, cuneate at the 

 base from a small discoid holdfast, irregularly dichotomo-fiabellate, the 

 segments mostly 5-7 mm. broad, entire, dull reddish in color ; internodes 

 short, 1.0-1.5 cm. ; apices rounded ; fronds 300-400 fi thick in cross section, 

 medulla of large, thin-walled cells, cortex of essentially a single layer of 

 brick-shaped cells about 12 by 5 /x; cystocarps spherical, usually marginal, 

 about 1000 fi diam., with a small, slightly raised ostiole; tetrasporangia 

 unknown. 



Type: D. 141a, in a 4-30-meter dredge haul, off Tiburon Island 

 near Turner's Island, Jan. 25, 1940. Herb. AHF no. 37. 



D. 83, dredged in 12-20 meters, outside Guaymas Harbor, Jan. 23, 

 1940; D. 265, dredged in Mejia channel, Puerto Refugio, Jan. 28, 1940; 

 D. 371, dredged in 22 meters, Tepoca Bay, Feb. 4; D. 339, dredged in 5 

 meters, San Felipe Bay, Feb. 2. 



In color and habit this species very closely resembles a Rhody/nenia, 

 and until cystocarps were found was confused with that genus. The typi- 

 cal gracilarioid gonimoblast development, however, is clearly indicated in 

 sections of cystocarps of several collections. 



This species seems morphologically related to the other broad, com- 

 planate Gulf species, Gracilaria Vivesii and G. Johnstonii, but is much 

 smaller throughout than those plants. 



Gracilaria Hancockii sp. nov. 

 Plate 65, Fig. 2 



Frondes 7-15 cm. altae, tenues, inferne cylindratae, superne complanatae, axi- 

 bus paucis e disco basali orientibus, multifarie ramosis, basim teretibus, 800-1200 n 

 diam., superne complanatis usque ad 2 cm. latis, apicibus acutis attenuatisque; 

 cystocarpiis protrudentibus e disco frondis, 1500 |i diam., carpostomio parvissimo. 



Plants 7-15 cm. high, slender, cylindrical below, flattened above, from 

 a small, solid, discoid holdfast, several main axes arising directly from the 

 holdfast or from a very short, thick basal stipe; axes branching loosely, 

 multifariously, terete at the base, 800-1200 fi in diam., becoming com- 

 pressed to flattened above and to 2 mm. broad; apices acute, attenuated; 



