This typical Pacific coast species is met with from Uruguay and 

 Chili to British America. It is very variable as to size and size of the 

 oospore. There seems in most forms to be a decided tendency to 

 dilatation of the leaves, but in all forms wherever found the surface of 

 of the oospore is very minutely granular. The stations reported in the 

 Braun-Nordstedt " Fragmenta " are Orizaba, Mexico, Mueller, 1853 ; 

 Big Sandy River, Missouri Plains, Fendler, 1849; Monterey, Cal., 

 Bolander, 1865 ; Basin San Francisco Water Works, Bolander, 1865 ; 

 Mexican boundary, Coppermine Creek, southern New Mexico, west of 

 the Rio Grande, Wright, 1851-2; the var. inflata, near Tacubaya, 

 near the City of Mexico, Schaffner, 1854, and in ditches near Chapul- 

 tepec, Potts, 1854. 



In addition I have received specimens from Sau vies Island, Oregon, 

 J. and T. J. Lowell, 1882 ; San Catalina Island (var. inflata), Brande- 

 gee, May, 1890; Sand Coulee, Montana, August, 1891 ; 



Lake Merced, near San Francisco, ; San Luis Potosi, Mexico, 



September, 1890, Pringle. 



In Uruguay the species was collected in 1839 by Gaudichand and 

 Twedie; in Buenos Ayres; in Argentina; in Cordova ; Bolivia, etc. 

 Spegazzini reports a var. laguroides from Uruguay, but the speci- 

 mens distributed by Migula, Sydow and Wahlstedt, No. 26, do not 

 differ from other collections, notably those from Mexico by Pringle ; 

 the verticils are remote and contracted, a not uncommon form hardly 

 characteristic of a variety. His "var." zonata, also from Uruguay, is 

 a form with zonular incrustation, frequently noticed in collections of 

 many species of Nitella and naked-stemmed charge. 



The specimens from Oregon bear oospores averaging 440 long by 

 410 broad ; those from Montana 340 long by 306 and even 260 broad ; 

 from Oregon, 7-8 ridges ; from Montana, 6 ridges all minutely 

 granular. 



Plate. Fig. I, portions of fertile verticil >( 25 ; Fig. 2, copied from Braun- 

 Nordstedt Fragmenta an upper view of a verticil, showing two sorts of leaves; Fig. 

 3, an oospore >( 50. 



NITELLA DILATATA, sp. nov. 



Plants diffusely branched 6 to 10 inches long; stems i to 2 mm. in 

 diameter ; lower verticils consist of 6 leaves which are at times simple, 

 at times once divided ; but without any "adventitious" leaflets, hence 

 falsiy heterophyllus ; fertile verticils contracted to dense masses, like 

 ' ' heads, ' ' long over-topped by the more slender fertile leaves ; leaves 

 of the fertile verticils all once divided, the terminal leaflets, in number 

 2 to 5, usually 3, somewhat inflated below, tapering above to a sharp 



