FK !:> II -WATER ALG.K OF THE UMTI 1> STATES. 183 



. i'. mi-ri.<m/.fi/)/i/i-u, Woun, Botanical Report of the United States Geological Ex- 

 ploration of the Fortieth Parallel, p. 415. 



JIuli. In torretibu8, Diamond llauge(alt. 6000 ft.), Rocky Mountains; (Sen-no Watson) \\ <>{. 



Thallus ample, broadly expanded, membranaceous, dilute green, tbin, radiately and irregularly 

 ])licate with Us outline often somewhat rounded; its margin undulate or at times almost 

 erefiate; the cells irregularly oval or angular, destitute of nucleus, quarteruary and obscurely 

 arranged in families after the manner of a merisiuopedia, 



Remark*. The largest fronds of this species that have come under my notice 

 arc about three inches long hy two broad, thin, easily torn, and not all gelatinous. 

 The portion hy which they have been attached is very evident, near one of the 

 margins, and from it broad undulations or folds radiate. Sometimes the frond is 

 split up into palmate, lobe-like parts. 



The cells are not closely approximate, but are placed in a homogeneous translucent 

 membrane, in such a way as to remind one of a Merittwpedia, 



I do not feel certain that this plant is distinct from U. orlriculata of Rabenhorst, 

 though for the present I have preferred so to consider it. His description is very 

 brief and incomplete, as is also the original one of Thuret, which I have con- 

 stilted. Prof. 11., however, gives U. latissima of authors as a synonym of U. or- 

 liriilnin, and certainly this plant is distinct from U. latissima, Harvey, of our 

 coast. Again it seems impossible that a plant growing near the summit of the 

 Km ky Mountains should be identical with one found on the coast of France. 

 1'rnf. Sereno Watson found this plant growing on rocks in a mountain stream of 

 the Diamond Range, at an altitude of 6000 feet. 



Genus ENTEROMORPHA, LINK. 



Thallus membranacens, tubulosus vcl ntricaliformis, basj affixus (saltern initio, postca saepc lil>ere 

 n.-it.i!i-i. e cellulnrum strato unico compositus, saepe raraosus, baud raro ramosissimus. I'rnpogatio 

 /niiliis. II.ee zoogonidia proceantur in cellulis quibusdam 8-16 cytioplasmatis divisione 

 a, in polo antico rostriformi ciliis duobus corpus duplo supcrantibus pradita. (R.) 



Thallus membranaceons, tabular or bladder-shaped, affixed by the base (at least in the beginning, 

 often afterwards floating freely), composed of a single stratum of cells, often branched, not rarely 

 very much branched. Propagation by means of zoospores, 8-16 of which are formed by the 

 repeated division of the protoplasm of a cell Their anterior beak-like portion provided with two 

 cilia whose length is not less than twice that of the body. 



K. inlcMtinalis, (LINN .) LINK. 



K. tcrrs, forma et magnitudine admodum varia, ssepe pedalis etiam supra, leptodcrma, saturate 



Tel pallide viridis, lilifonnis vel intestiniformis, plana vel bullosa; cellulis 3-5-6 angularibus. 



(R.) Species mihi iynota. 

 /Worn. 0.00048" 0.0008". (R.) 

 Syn. E. intestinalis, (LiNN-SVs) BAILEY, Silliman's Journal, N. S., Vol. III., ct RABENHOROT, 



Flora Europ. Algarnm, Sect. III. p. 312. 



Hab Hudson River, from Newburgh to New York City; Xarragansett Bay, Rhode 



I -land; Bailey. 

 Terete, very various in size and shape, often a foot or more in length, smooth, deep or pale 



preen, filiform or intestiniform, plain or Imllose ; cells 3-5-6 angular; their diameter 0.00048' 



0.0008". 



