142 ECTOCARPACEiE.— EcTocARPus. iv. 



or rarely alternate ; propagula (spores?) elliptical, dark coloured, sessile. liarv. 

 Phyc. Brit. t. 200. /. Ag. Sp. Alg.\,p.2\. 



Hab. On Algoj, etc. between tide-marks, in rock pools. Boston, Dr. Silas 

 Durhee. (v. v.) 



Filaments capillary, not very densely tufted, from four to eight inches long 

 much branched, with a principal stem and lateral decompound branches. All the 

 divisions mostly opposite and spreading. Propagula ellipsoidal, dark-coloured, 

 plentifully scattered on the ramuli. 



9. EcTOCARPus Diirkeei ; tufts not very dense ; filaments robust, decompound, 

 much branched, the branches and the lesser divisions alternate ; the angles acute 

 and ramuli erecto-patent, attenuated, alternate or secund ; articulations of the 

 branches shorter than their breadth ; propagula elliptic-oblong, obtuse, subsessile, 

 constricted at the base, transversely striate. (Tab. XII. F.) 



Portsmouth, New Hampshire, Dr. Durkee (No. 35). (v. s. in Herb. T. C. D.) 



Ttifts two inches long, hair-like, spreading. Filaments much branched, with an 

 evident leading stem, and decompound, alternately divided branches ; the main stem 

 and larger branches much more robust than the branches of second or third order, 

 and remarkable for the shortness of their articulations, whose dissepiments are 

 somewhat constricted. The angles are all acute, and the branches and ramuli con- 

 sequently erect. The propagula are borne toward the base of the smaller branches, 

 and several are generally found together on the same branch. Colour olive-green. 



The ramification of this plant is most like that of E. Littoralis, but the fruit is 

 nearer in form to that of E. granulosus. It seems a distinct species, so far as I can 

 judge from the examination of a single specimen. 



Plate XII. F. Fig. 1, Portion of a filament of Ectocaepus Durkeei, magnified ;, 

 Jig. 2, minute portions with propagula ; f.g. 3, a propagulum ; the latter figures 

 highly magnified. 



10. Ectocarpus MitchellcB ; tufts feathery ; filaments very slender, decompoundly 

 much branched, the branches and their lesser divisions alternate ; the ultimate 

 ramuli approximated ; angles wide, and branches and ramuli patent ; ramuli 

 attenuate, articulations of the branches twice or thrice as long as broad, of the 

 ramuli once and half as long, propagula elliptic-oblong or linear, quite sessile and 

 very obtuse, transversely striate, several together. (Tab. XII. G.) 



Nantucket, Mass., Miss A. Mitchell, (v. s. in Herb. T. C D.) 



