42 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 17 



with "rhi'zoidal" filaments; plants apparently dioecious; carpogonial 

 branches 5-6 celled, arising laterally from a branched vegetative lateral, 

 with a long trichogyne, the cell of the vegetative lateral subtending the 

 carpogonial branch producing early a whorl of short, vegetative cell- 

 rows which continue to develop after fertilization to form a cluster of 

 sterile filaments somewhat smaller than the gonimoblast cluster and just 

 below it, thus giving the effect of a double cluster to the mature gonimo- 

 blast, the cystocarp proper being raised, however; gonimoblast developing 

 from the terminal cell of the carpogonial branch, the lower cells of the 

 carpogonial branch becoming enlarged but retaining their form and 

 being dimly visible in fairly late stages between the gonimoblast cluster 

 and the vegetative filament cluster (involucre) below; antheridia not 

 seen. 



Type: Holotype is Dawson 2875, October 10, 1946, on sheet 

 50464, including vial 1651 and slides 933-936, in HAHF. 



Type locality: In beach drift at Punta Santa Rosalia, Pacific 

 Baja California, Mexico. 



This plant shows in its habit and assimilatory filament characters an 

 affinity with Liagora orientalise but in other respects, notably in the 

 development of the involucral filaments, it is markedly different. Dr. 

 Isabella Abbott has examined the plant and has suggested in a personal 

 communication that the peculiar involucral development, together with 

 the habit, constitute sufficient distinction to set it apart as a new species of 

 Liagora. I take pleasure in naming it for her in recognition of her careful 

 studies in this genus. 



Liagora californica Zeh 



Plate 2, figs. 16-17; Plate 16, fig. 1 



Zeh, 1912, p. 271 ; Dawson, 1945, p. 93. 



Thalli saxicolous, 1 to a few fronds from a discoid base, 6-16 cm. 

 high, repeatedly dichotomously branched at irregular rates, without pro- 

 liferous lateral branchlets, cylindrical, about 1 mm. in diameter or some- 

 what less, heavily calcified extraperipherally in regions 2 cm. or more 

 below the tips, the terminal parts reddish, calcified within; assimilatory 

 filaments moniliform, corymbosely branched, 8-12 /a in diameter, the 

 outer cells clavate to ovate; plants dioecious; antheridia semi-capitate, 

 borne in small groups on elongate pedicels from the ultimate assimilatory 



