-5- 
Ccranium va gab unde Dawson 24843c. This material is somewhat 
~ more slender than Ehiwetok specimens and has nodal bands 
more like those of the material reported from Isla San Bene- 
dicto, Mexico,, yet the agreement is generally satisfactory. 
Growing with Caulerpa serrulata. 
Cer; 
p. 24840a. Fertile 
)ar- 
tetrasporangial material app< 
ent ly near C. personatum Setch. & Card. The agreement is good 
except that the descending appendages within the axial cells 
were not observed. The tetrasporangia are at first abaxial, 
then whorled and involucrate. Growing with Caulerpa urvil - 
leana. 
Griffithsla sp. 24864c, sterile. 
Herposiphonia secunda (Ag.) Ambronn 24733 (richly developed); 
' 24805 ;.24829 (richly developed); 24834. 
Beterosiphonia wurdemannii var. laxa Borg. 24748 (mixed with 
Herposiphonia); 24741 (in mixture); 24854a (on old Turb inaria ); 
’ 24853 . R "' 
The following determinations and notes on 
Polysiphonia are provided by Dr. George J. Hollenberg 
of the University of Redlands, California 
1 
Polysiphonia ferulacea Suhr 24866a. This determination is 
probably correct if Tseng, Cribb and others have been correct 
in their identifications of Pacific specimens. It should be 
considered tentative, however,-until male plants are found. 
Polysiphonia flaccidissima Hollenberg 24867- This determination 
is probably reliable although the segments are shorter (l.O- 
1.5 diameters) and the trichoblasts are not well developed and 
with tapering tips. 
Polysiphonia mollis Hook. & Harv. ?? 24823- This identification 
is doubtful because of (l) small size; (2) obvious sympodial 
branching; ( 3 ) very long, continuous tetrasporangial branches. 
Laurencia nana Howe 24761. The cortical cells are of the non¬ 
palisade type, although an error occurs in expressing this in 
Dawson 1957> p. 124. 
