240 FLORA OF MOUNT DESERT. 



D. undulatum (J. Ag.), Reinke. Punctaria latifoUa, var. 

 Zosterce, Farlow's Manual, 64, at least in part. 

 On Zostera. Little Cranberry Isle (Collins) ; — Somes Sound 

 (Holden). 



SPHACELARIACE^. 



SPHACELARIA, Lyngb. 



S. radicans (Dillw.), Ag. 



Common on rocks near Seal Harbor (Collins). 



ECTOCARPACE^. 



ECTOCARPUS, Lyngb. 



E. confervoides (Roth), Le Jolis. 



Common on Chorda, Zostera, etc. Seal Harbor, and else- 

 where (Collins); — Southwest Harbor (Holden). 



Var. siliculosus, Kjellm. 



On Zostera. Little Cranberry Isle (Collins) ; — Southwest 

 Harbor (Holden). 



E. fasciculatus, Harv. 



Common on Rhodymenia, Laminaria, etc. Seal Harbor, and 

 elsewhere (Collins) ; — Sea Wall (Holden). 



ASCOCYCLUS, Magnus. 



Resembles Myrionema, but the sporangia terminate upright 

 filaments or their branches, instead of rising directly from the 

 basal layer. 



A. orbicularis (J. Ag.), Magnus. 



Basal stratum of one layer of cells, from which arise colorless 

 hairs, unicellular saccate paraphyses, and shortly stipitate 

 plurilocular sporangia, usually of a single series of cells. On 

 Zostera, Little Cranberry Isle (Collins). 



