THE GREEN ALGAE OF NORTH AMERICA 417 



when the ramuli as a whole are of one or more of the numerous 

 forms found in this species, there will always be a few of the 

 characteristic shape near the base of the frond. 



Var. TYPICA Weber, 1898, p. 326 ; Vickers, 1908, p. 27, Pis. 

 XLIV, XLIVb. Frond and its branches with naked base, 

 otherwise surrounded by sub-navicular ramuli, in 3 ranks 

 (rarely in 2, 4 or 5 ranks) ; length of ramuli up to twice the 

 diameter of the axis. W. I. India. 



Var. TURNERI Weber, 1898, p. 330. Frond slender, ramuli 

 in 3 or 4 ranks, sub-navicular or conical, small, length hardly 

 equalling the diameter of the axis, appressed, or nearly so. 

 Fla., W. I. 



Var. SERRATA (Kiitz.) Weber, 1898, p. 331. Frond slender, 

 with elongate branches, dichotomous, alternate, or fascicled ; 

 in places naked, but usually near the summit with ramuli in 2 

 or 3 ranks. Ramuli small, erect or horizontal, sub-navicular, 

 opposite or alternate ; length hardly equalling the diameter of 

 the axis. Guadeloupe. Venezuela. 



Apparently a reduced and depauperate form of vars. typica 

 and Turneri, due to growth under unfavorable conditions. 



Var. MAMMILLOSA (Mont.) Weber, 1898, p. 332 ; Alg. Am.- 

 Bor., No. 96. Primary axis of the frond naked or covered with 

 mammilliform or obtuse ramuli ; branches issuing at acute 

 angles, covered from the base with obovoid or sub-navicular, 

 mucronate, erecto-patent ramuli, in 5 or more ranks ; length of 

 ramuli hardly equalling the diameter of the axis. 



Forma TYPICA Weber, 1898, p. 332. Base of central axis 

 surrounded by mammilliform ramuli. Fla., W. I. 



Australia, So. Pacific. 



Forma NUDA Weber, 1898, p. 332. Base of central axis not 

 surrounded by mammilliform ramuli. Fla., W. I. 



Var. ERICIFOLIA (Turner) Weber, 1898, p. 335. Frond sur- 

 rounded by multiseriate cylindrical ramuli, appressed to the 

 axis ; length about the diameter of the axis. W. I. 



Var. LYCOPODIUM (Ag.) Weber, 1898, p. 335. Frond tall, 

 generally little branched, ranruli erecto-patent in two ranks, or 

 erect in several ranks, sub-navicular at the base of the frond, 

 cylindrical above, 2-6 times as long as the diameter of the usu- 

 ally slender axis. 



Forma ALTERNIFOLIA Weber, 1898, p. 33 6 -* Frond dichoto- 



*Bbrgesen, 1907, p. 368, fig. 17, proposes the name forma plumarioides 

 for forma alternifolia and forma elegans of var. Lycopodium, with de- 

 scription as follows : Branches long, rather weak ; ratuuli in 2 or 3 rows, 



