1 882.] On 

 companying 



in forms of CJiara coronata. 365 



taken from Professor Peck's speci- 



The bracts are shorter and unilateral, the nuclei smaller, 550 p., 

 ut the coronula seems less elongated; whether the plant 

 till continues to vary, remains for farther investigation to es- 



vi. Forma macrocarpa, macroptila, verticillata, laxior, leiopy- 

 rena. This very common northern form was collected in Canada 

 by Professor Macoun ; it is slender, diffuse, with long leaves of 

 4-5 articulations, verticillate bracts much longer than the sporan- 

 gium, often two or three times its length, the anterior bracts 

 longer than the lateral, the posterior large but much shorter. 

 Nucleus precisely like the Saranac form (v), and about the same 

 size, 620-650, ribs 9-10, scarcely prominent. 



One collection of this form from the far west of Canada is 

 completely incrusted with lime, and when dry is gray and very 

 brittle ; another from Eastern Canada has a peculiar zonular in- 

 crustation but usually the plant is perfectly smooth even in water 

 containing considerable lime. The habit of growth varies ex- 

 ceedingly, some are delicate, diffuse and pellucid, others stout, 

 thick, compact, and in deep water often attain a length of 4 to 5 

 feet (Litchfield lake, Ct.). This is our most common form, though 

 the cells of the coronula are usually connivent, as in the next 

 form, and the bracts may be unilateral on some nodes of the same 

 plant. 



