lU I r. KSU-WATER ALG.E OF THE UNITED STATES. 



" Frond sniallci- tliaii V. Elircnbcrgii, stout, five or six limes as lon.!^ as broad, lunately curved, 

 cxtreiiiilies tapering, uiijier margin convex, lower coucave, witli a central injlation, ends 

 rounded; large grauules, conspicuous, in a single longitudinal series; e. f. colorless, without 

 stria;, suture not evident. L. A"— bo"- K. sh"— ?Jf"- Archer." Pritchard's Infmorm, 

 p. 748. 



C. Leiblesnii, Ktz. 



C. priore minus, seuiilunare, magis incurvum, ventre inflate, ad utrumque polum largius attenn- 

 atuni, apicibus achrois acutis; vesiculis chloropliyll in quoqae crure 5-6, in serie simplici 

 axillari dispositis; locello magno, apices versus sito, corpuscula numerosa iucludente. (11.) 



Diam.—^\l^". 



Syn.—G. Leihleiini, Kutzing. Rabeniiorst, Flora Europ. Algarum, Sect. III. p. 132. 



£a6.— Georgia; Rhode Island ; Bailey. Pennsylvania; Wood. 



" Frond somewhat stout, distance between the extremities six or eight times the breadth, 

 crescent-shaped, much curved, rapidly attenuated, upper margin very convex, lower very con- 

 cave, often with a slight central inflation; ends subacute ; large granules, in a single series; 

 fillets few or indistinct; e. f. somewhat straw-colored, without strife; suture evident. Spo- 

 rangium orbicular." Archer. 



Remarh. Fig. 6, pi. 12, represents this plant, magnified 260 diameters. 



4. Cellulse maxime curvalse, ventre non tmnidae. 

 4. Cells most curved, the belly not tumid. 



C. Diniiac, Ehrb. 



C. anguste fusiforme, semilunare, utroque polo valde attenuatnra, apicibus subacntis ; cytioder. 

 mate achroo (vel dilutissime umbriuo), striis subtilissiuiis medio interruptis praidito, in media 

 parte striis transversalibus 3-5; vesiculis in quoque crure 6-7, in serie unica axili dispositis; 

 laminis chlorophyllaceis pluribus, saepe flexuosis; locello indistincto, corpusculis pluribus 

 yivide mobilibus. (R.) 



i)wm.— Lat. 75V' =-00053". Long, ^ff/ = .00082". 



Syn. — C. Dianse, EnRENBERG. Rabenhorst, Flora Europ. Algarum, Sect. III. p. 133. 



Hah. — Georgia ; Florida ; Rhode Island ; Bailey. Pennsylvania ; Wood. 



Frond crescent-shaped, six or eight times as long as broad, much curved, rapidly attcnnated; 

 upper margin very convex, lower very concave without a central inflation ; ends subacute 

 with a very slight emargination at the upper outer extremity; large granules in a single 

 series; empty frond, somewhat straw-colored, or faintly reddish, without striae, suture evident. 

 (A.) 



Remarks. — Mr. Archer marks C. Venus, Ktz., as a doubtful synonym of this 

 species ; not having Prof. Kiitzing's work at hand, I do not know whetlier G. 

 Venus, Ktz. is really the following species or not. The two forms here hiown as G. 

 Dianer, Ehrb. and C. Venus, Ktz. are, however, I think sufficiently distinguished. 



Fig. 4, pi. 12, represents this species of desmid. 



C. Yeniis, Ktz. 



C. parvura, plus minus gracile, semicirculare, oetiess-duodecies longins qnam latum, in apices 

 subacutos ffiqualiter sensimque attenuatuin ; cytiodcrmate tenui.'^lffive ; laminis chlorophylla- 

 ceis obliteratis ; vesiculis in quoque crure 3-4 ; locello distincto corpusculis 4-6 replete. (R.) 



Diam.— .0004". 



