I K KS1I-U ATKK A I. ;.!: OF THE UNITED STATES. 129 



l, 0.0019" 0.00-Ji' <i: ) 



ii. ('. Hr-i.i.-fiitii, MKNUIIIIKM. KAHKNIIORST, Flora Europ. Algarum, Sect. III. p. 158. 

 7/,//,._Whit,. Mountain-, V n llaui|>.-hiiv, (I r . F. W. Lewis) Wood. 



From! somewhat longer than broad, constriction deep, linear; segments scmiorbicular, rough 

 all over, with Mmirwhut elongate conical scattered pearly granules; c. v. elliptic. (A ) 



A'///-?//.. 1 '!:,'. (i, pi. 21, represents an empty frond of this species, magnified 

 1.~>l) diainrti T-. 



<'. Hiiborbiculare, u . 



C. parviiiM, suliorlu'culare, paalo longius quam latnm, cum margine enorraiter crenato vel 

 rrt-nato-undulato; semiccllulis a latcro orbicularibus, a vertice elliptici; sinu extrorsum 

 august issimt) sod introrsum nonnihil excavato ; cytioderraate crasso, sparse verruculoso; 

 ^ranulis in semicellulis singulis subdistantibus et in scriebus clongatig, duabus (interduni 

 unica) externis curvatis, et in scriebus duabus internid brcvibus et rcctis. 



/>iam._Lat. T ,' V' - .0012" ; lat. T1 ' V - -0013". 

 ,syi. C. orbiculare, WOOD, Proceed. Acad. Nat Sc. 1870. 

 //,//>. In lacn " Saco," New Hampshire, (Lewis.) 



Small, suborbicular, a very little longer than broad, with the margin irregularly crenate, or 

 n-1-nate undulate ; semicells from the side orbicular, from the vertex elliptical ; sinus very 

 narrow, but within somewhat excavated ; cytioderm thick, sparsely coarsely granulated ; 

 irnmiili's subdistant, in each cell arranged in one or two curved marginal scries and in a cen- 

 tral group of two or three short rows. 



/,'- ,<///-. The arrangement of the granules in this desmid is peculiar, one, of 



soinrtimi > two rows of large obtuse pearly granules are placed at rather wide in- 



N aloiii; the whole outer margin, and then in the centre of each semicell is a 



irnmp of two or three, or even more short straight rows of three or four similar 



nit rather smaller granules. The isthmus is rather broad and short; sometimes it 



on it one or two granules. 



1 -'ig. 9, pi. 21, represents an empty frond of this species, magnified 750 diame- 

 ters ; 9 a, the outline of the end view of the same. 



4 . trtroplitlinlituim, (KT/ ) P.KEB 



C. tortiam partcm circa longins quam latum, profunde constrictnm ; sinu angnsto, plerumque 

 sublineare ; ambitu obtuse crenato; semicellulis nonnihil scmicircularibus, venire subplanip, 

 dorso rotundatis; cytiodermato verruculoso; verruculis tnagnis, obtusis, subordinatim dispo- 

 sitis. 



Syn. C. tetrophthalmum, (KtTZiNo), BBBISSON. RABENHORST, Flora Enrop. Algarum, Sect. 

 III. p. 159. 



Hab. New Jersey ; Wood. 



About one-third longer than broad, deeply constricted ; sinus narrow, mostly snblinear ; margin 

 obtusely crcnated ; seraicells somewhat semicircular, belly nearly even, dorsnm rounded ; 

 cytioderm warty ; prominences large, obtuse, arranged somewhat regularly. 



Remarks. The only specimens I have seen, and I believe the only ones hitherto 



17 July. 1871 



