MlCROSPORA 179 



September; Central Park, June (6 13 A), October (664A) ; Pelham 

 Bay Park, May (394B), September (486). 



This species has been observed repeatedly in several stations, 

 always showing a very constant character, and never mixed with 

 other forms. It is the only Microspora that has been observed in 

 the herbaceous grounds of the New York Botanical Garden, in a 

 stream where Spirogyra, Tribonema, Draparnaldia, and Myxonema 

 abound. It is well marked by the nearly square shape of the 

 cells (in optical section), and by the fine bead-like edge of the 

 chromatophore. 



Young specimens collected in October showed a slightly nar- 

 rowed basal cell imbedded in mucus, appearing somewhat like a 

 small Ulothrix in the manner of attachment. It is probable that 

 these plants germinated from akinetes which had lain dormant 

 during the heat of the summer. 



Microspora quadrata is perhaps very nearly allied to, if not 

 identical with the M. punctalis of Rabenhorst and recent authors. 

 There is considerable doubt, however, whether it is the Conferva 

 punctalis of Dillwyn and it is almost certainly not C. punctalis 

 Mueller (Nov. Act. Acad. Sci. Imp. Petrop. 3 : 90. pi. 1. f 1. 

 1788) to which Dillwyn's figure and description supposedly 

 applied. Mueller's species was probably a form belonging to the 

 Mougeotiaceae. Agardh (Spec. Alg. 83. 1824) was of the opinion 

 that C. punctalis Dillw. //. 5/. and Lyngb. pi. /j.6 y was a species of 

 Zygnema. 



Doubtful Forms 



Microspora vulgaris Rabenh. Krypt. Flor. Sachs. 1 : 245. 

 1863; Flor. Eur. Alg. 3: 321. 1868. 



Conferva vulgaris Kirchn. Krypt. Flor. Schles. 2 1 : 79. 1878. 

 Wolle, F. W. Alg. 142. pi. 21. f. 6-13. 1887. 



Conferva Farlowii Wolle, Bull. Torrey Club, 6 : 140. 1 887. 



C. vulgaris Farlowii Wolle, F. W. Alg. 142. 1887. 



Microspora Farlowii Rabenh. Alg. Eur. 2566. 1878. 



All the above as represented in the Wolle herbarium appear to 

 be forms of Tribonema ; also Tilden, Am. Alg. 21. 1894, at least 

 for the most part. Saunder's figure of M. vulgaris Farlowii (Flora 

 of Neb. pi. 22. f j. 1894) is evidently Tribonema. 



Microspora fugacissima (Roth) Rabenh. Flor. Eur. Alg. 3 : 

 321. 1868. 



