492 HowWE: PHYCOLOGICAL STUDIES 
Cladophora ovoidea Kiitz. (type from the island of Féhr, North 
Sea) has, according to its original describer, primary filaments that 
are 1/20’”” (112u) thick and upper branches 1/40’”” (56) thick,* 
and his latert figures of the species bear out this general description 
of its dimensions, though one of the cells of the main filament 
figured, according to the magnification given, reaches a diameter 
of 1504. We have seen no European specimens of C. ovoidea, but 
are unwilling at the present time to identify with this species a 
Lower California plant with filaments and branches averaging 
twice as thick as those of the plant described and figured by 
Kiitzing, and with filaments so little constricted at the septa (in 
a soaked-out condition, at least) that no one would think of de- 
scribing any of the cells as “ovoid” (Kiitzing, Phyc. Gen. 266). 
Also, according to Kiitzing’s figure, the branching in C. ovoidea 
is more fasciculate than in C. MacDougalii, the ultimate lateral 
branchlets are less tapering and less rigid, and the main axes do 
not show the long-excurrent prolongations of the Baja California 
species. 
CLADOPHORA TRICHOTOMA (Ag.) Kiitz. Sp. Alg. 414. 1849 
Conferva trichotoma Ag. Syst. Alg. 121. 1824. 
Fragments referable to this or to some closely allied species 
are mixed in with a specimen of Centroceras clavulatum from La 
Paz in the herbarium of the New York Botanical Garden, ex herb. 
C. L. Anderson, collector unknown. The intertangled filaments 
are 190-3004 in diameter, di- or trichotomous at nearly every 
joint, with occasional short and blunt lateral branches I-3 cells 
long and of scarcely less diameter than the parent filament; cells 
mostly 2-5 times as long as broad, usually constricted at the 
septa, the upper often ovoid. The plants are rather coarser and 
the cells are relatively shorter than called for by Kiitzing’s descrip- 
tion and figures for the species in question. 
HALIMEDA DISCOIDEA Decaisne, Ann. Sci. Nat. II. 18: 102. 1842. 
Howe, Bull. Torrey Club 34: 495-500. pl. 25. f. 11-20; 
pl. 26 107 
La Paz, Vives 4. 
The segments are here mostly quadrangular-oblong or cuneate- 
SE a ROT enter tshaetsion., Pel Mice rcvbrnell 
* Kiitzing, Sp. Alg. 393- 1849. 
T Kiitzing, Tab. Phyc. 3: 26. pl. 02. f. 1%. 1853. 
