to 12 cm. long; hairs few or lacking, short with bulbous bases; 

 corticating branches few or lacking; monoecious; carpogonia on 

 primary lateral branches in the outer part of branch-whorl, sub- 

 tended by large cells and numerous lateral branches; trichogyne 

 clavate. 



In Sphagnum bog pools; attached to stones in slowly flowing 

 water. Mich., Wis. 



Batrachospermum moniliforme Roth 1800, p. 450 

 PL 136, Fig. 3 



Plants stout, richly branched, with well-developed whorls of 

 branches presenting a distinct beaded or moniliform appearance 

 macroscopically; plant mass gray-green, violet-green, or brownish; 

 plant masses up to 10 cm. long, forming streaming tufts (frequently 

 in swiftly running water ) ; inclosed by copious, soft mucilage; plants 

 annual; monoecious; carpogonia developed in inner part of the 

 branch-whorls, terminal on short lateral branches in the axils, with 

 a clavate or lageniform trichogyne; carpospore masses, dense, scat- 

 tered throughout the plant; branches ending in long setae with a 

 swollen base. 



This is the most common species of the genus in the region. It 

 often occurs in flowing water, where it may form extensive beds on 

 stones and gravelly bottoms. 



On submerged wood in streams; also in lakes. Mich., Wis. 



Batrachospermum vagum (Roth) C. A, Agardh 1824, p. 52 



PI. 135, Figs. 7-11 



Plants freely branched, as much as 20 cm. long, forming dark 

 olive- or gray-green arborescent masses inclosed in copious mucilage 

 and forming soft, streaming thalli; whorls of branches well- 

 developed, forming globose nodal masses, the branches composed 

 of ovoid or ellipsoid-ovoid cells, ending in long hairs; the whorls 

 quite separated in the lower part of the plant, becoming closer and 

 coalesced distally; plants monoecious, the branch bearing the carpo- 

 gonium consisting of 7-14 cells, developing centrally in a whorl of 

 branches, the carpogonial cell bottle-shaped with a spatula-shaped 

 trichogyne; antheridial units globose, few in a cluster, cut off from 

 the tips of lateral branches; carpospores many, forming a dense 

 mass within the center of a whorl. 



Attached to submerged logs in flowing water; fruiting late in 

 summer. Mich., Wis. 



FAMILY LEMANEACEAE 



In this family the thallus is a branched, solid or hollow cylinder 



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