256 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 12 



LOMENTARIA Lyngbye, 1819 

 Lomentaria Baileyana (Harvey) Farlow 



Taylor 1937, p. 308, pi. 35, fig. 10, pi. 41, fig. 4, pi. 43, fig. 6. 



Mexico: Is. Revilla Gigedo, dredged from 57 meters at sta. 2829, 

 Albatross Exped. no. 28 (cystocarpic), 1 May 1888. Costa Rica: a 

 few small pieces dredged off Pto. Culebra, no. 34-525, 24 Mar. 1934. 



GHAMPIA Desvaux, 1808 



Ghampia parvula (C. Agardh) Harvey 



Taylor 1937, p. 310, pi. 43, figs. 8-10. 



Ecuador: Esmeraldas, dredged one specimen at Bahia San Fran- 

 cisco, no. 34-488, 11 Feb. 1934. 



Ceramiaceae 



Plants usually bushy, filamentous branches uniseriate, naked or corti- 

 cated, the cortex if present developed from nodal segments on the per- 

 sistent axial row, restricted or spreading over the internode ; growth com- 

 monly from an evident apical cell ; sporangia superficial or stalked, some- 

 times immersed in the nodal cortication, tetrapartite, tetrahedral or oc- 

 casionally developing polyspores; spermatangial branchlets more or less 

 in colorless clusters; carpogenic branches of four cells upon a supporting 

 cell which produces sterile and auxiliary cells near the carpogonium ; 

 cystocarp naked or immersed in a jelly, or partly surrounded by involucral 

 cells or filaments, of one or more groups of gonimoblasts with the outer 

 cells producing the carpospores. 



KEY TO GENERA 



1. Evidently segmented, the oval to spherical coenocytic segments 

 visible to the naked eye Griffithsia 



1. Segmentation of the axis obscure, the segments, if large, covered 

 by corticating cells 2 



2. Plants filamentous in habit, sparse to bushy 3 



2. Plants spongy in structure, flabellate in habit . . . Haloplegma 



3. Uncorticated, or with rhizoidal cortication 4 



3. Corticated by nonrhizoidal otugrowths from the nodes . .10 



4. Branching generally completely alternate 5 



