1 882.] On some American forms of Chara coronata. 359 



having verticillate bracts and an equally large nucleus. In the 

 Sandwich islands is found a delicate form in which the cells of 

 the coronula are much elongated, and approaching this form is 

 one collected in New Mexico by Wright. Besides the more dis- 

 tinct forms are many intermediate forms, difficult to place, pos- 

 sessing characters belonging to two or more varieties ; indeed the 

 forms of this species from different places are quite numerous. 

 We find the plant everywhere from Canada to Mexico and from 

 Massachusetts to California. 



One interesting fact is, that the plant in any given locality is 

 constant in its peculiarities, and though thousands of plants be 

 examined they will all be found to exhibit precisely the same 

 character. This is true not only of this species but of most 

 other species of Characeae ; thus in a pond filled with Chara 

 foziida A. Br., with long bracts and long terminal naked nodes 

 (Macroptila, Macroteles) all the plants will have the same pecu- 

 liarity and will keep it unchanged year after year, while a neigh- 

 boring pond perhaps only a few rods distant, may be inhabited by 

 another distinct but persistent form. 



A. Braun relates that Chara gymnopus var. Humboldtii A. Br., 

 collected by Gollmer in the same lake in which fifty-five years 

 before Humboldt had gathered it, presented precisely the same 

 characters. We have, however, noticed in one instance an appa- 

 rent difference in a form of C. coronata collected in precisely the 

 same locality in which it had been found twenty years before, 

 but there might have been a difference in the maturity of the 

 plants. This permanence of slight peculiarities may be owing to 

 the disagreeable odor and taste of the plant, which has often a 

 strong smell of sulphuretted hydrogen, rendering it offensive to 

 animals who might otherwise feed upon it and carry the seeds to 

 other localities ; and as the plants grow wholly under water, the 

 seeds are not liable to be carried by the wind. Hybridization 

 seems, therefore, to be infrequent and exceptional. These very 

 qualities, which serve to limit the spread of the Characeae, may 

 also have determined the persistence of very ancient forms and 

 limited their multiplication. 



The characters relied upon for distinctions betweeen varieties, 

 have been the development of the bracts, the size and striation of 

 the nucleus, and the character of the coronula of the sporangium. 

 The general aspect of the plant, size and length of stem, density 



