FRESH-WATER ALG^ OF THE UNITED STATES. 1G9 



diameters. Fig. 5 c is an outline of a pair of fertile cells enlarged to the same 

 extent. 



Sp. parrispora, Wood. 



Sp. articnlis sterilibus diaractro 2-4 plo loDgioribus ; fructiferis liaud tumidis, diamctro l-2i i)lo 

 lougioribus; fasciis spiralibus 4, angustis, nodosis, anlVactibus pluribus ; zygosporis parvis- 

 simis, ellipticis, diamctro 1^-2 plo longioribus; cytiodurmate utroque fine nee protcnso uec 

 re|ilicato. 



Diam.— Art steril 7|g5"=.003"; spor. diam. transv. yjg/— 7^3/= .002"— .0023",long. ^H^" 



30 " 



Syn. — S. parmspora, Wood, rrodromus, Proc. Am. Philos. Soe. 1SC9, p. 139. 



Ilab. — lu stagnis, Hibernia, Florida. (Wm. Canby ) 



Sterile joints 2-4 times longer than broad; fertile not tumid, 1-2^ times longer than liroad ; 

 chlorophyl bands 4, narrow, nodose; turns many; zygospores very small, elliptieal, 1^-2 

 times tonger than broad; cell wall not infolded at the end. 



Remarks. — I am indebted to Mr. Wm. Canby for specimens of this species, 

 which he collected in a pond in the Fine Barrens near Hibernia, St. John's lliver, 

 Florida. It is remarkable for the comparatively small size of the spores, which do 

 not nearly fill the perfectly cylindrical mother-cells ; indeed they are only about as 

 long as the latter are wide. This species closely resembles S. majiiscida, but is 

 larger, does not, that I have ever seen, vary liive it in the number of spores, and is 

 especially separated from it by the very small size of the latter. 



Fig. 7, pi. 15, represents a fertile pair of filaments of this species magnified 125 

 diameters. 



8p. majuscula, Ktz. 



Sp. pallide et sordide viridis, fructus tempore fuscescens ; articulis sterilibus diametro (0.002'2" 

 — 0.0025") 2^-4-10 plo longioribus; cytioderniate tcnui horaogcneo ; fasciis 3-4-5 (rarius 

 T), modo subreetis longitudinalibus, modo lasissime spiralibus, nodosis; zygosporis globosis 

 vel ovalibus. (R.) 



Syn. — S. majuscula, KiJTZiNO. Rabenhorst, Flora Europ. Algarum, Sect. III. p. 244. 



Hab. — Prope Philadelphia. ? 



Pale and sordid green, fuscescent at the time of fruiting ; sterile joints 24-4-10 times longer 

 than broad (.0022" — 0025") ; eytioderm thin, homogeneous ; spiral filaments 3-4-5 {^rarely 7) 

 partly straigUtish and longitudinal, partly la.\ly spiral, nodose ; zygospores globose or oval. 



Remarlcs. — Shortly after I commenced to study the fresh-water alga?, I found 

 below the city a fruiting Spirogijra, of which I preserved only a drawing, which I 

 have since identified as apparently specifically one with the European S. majuscida, 

 it differing only in not being quite so large; my measurement was ^-Jq^" = 0.002". 

 Not having any specimens at hand, I have copied the description from the work of 

 Prof. Rabenhorst. 



Fig. 1, pi. 15, was copied from the drawing alluded to. 



Sp. nitida, (Dn,Lw.) Link. 



Sp. coespitibus, lubrieis, saturate viridibns; articnlis sterilibus post divisioncni diametro snb- 

 8equalibu.s, ante divisionem 2-3 plo longiorilms ; articulis fertilis aliis simillibus, baud tumidis ; 

 fasciis spiralibus 4(3-4 R ), modice latis, anfractiljus 1-2; zygo.'^poris ellipticis. 

 22 August, 1873. 



