41 



+ 



large, equalling the number of the leaves, completely encircling the 

 stem ;' the nodes of the cortex numerous, armed with spines usually 

 three from each node, of about equal length, as long as the diameter 

 of the stem ; the spines so numerous that the stem is completely 

 hidden by them. Stipules double, directed upward and downw^ard, 

 two at the base of each leaf, the upper longer than the lower, as large 

 as the spines, about as long as the first internode of the leaves. 

 Leaves 8—10, usually 9, in a verticil, short, somewhat incurved; in- 

 ternodes 4—7, usually 5, corticated like the stem, haplostichous, ex- 

 cept the termmal segment, which is naked and simple, rarely articu- 

 lated, and with the whorl of bracts of the last- node, which are nearly 

 as long, forming a terminal tuft. Bracts verticillate, equally developed 

 all around the node, usually much longer than the sporangium, 

 except three very short extra bracts subtending the sporangium,' 

 which seem to stand in the place of the antheridium, sometimes the 

 middle one of these three " bracteoles " is elongated to nearly the 

 length of the sporangium. Sporangia oblong-oval with 15-16 whorls 

 on one side, coronula somewhat connivent (in American forms) rather 

 short. Nucleus black, with 12 to 15 sharp angles on one side; in 

 one form {pachyspcrmd) broadly oval, in another {leplosper?na) narrowly 

 oblong. Antheridia very rarely seen ; the plant propagating itself by 

 parthenogenesis. Dioecious. 



I have considered the American plant a distinct variety, on 

 account of its large seeds (nuclei 620 }.i long ; in the European forms 

 from 350 to 560 p. long) ; indeed, it seems to occupy a position nearer 

 the following species {Ch. evohitd) than the European forms do. 



The larger form ipacJiysperma) was gathered in i860 by the writer 

 on the shore of Great Pond, Montauk Point, Long Island. The pond 

 at that time was fresh, or slightly brackish from the occasional 

 breaking of salt water over the bar which separated it from the sea. 

 Since then an inlet has opened and the pond has become nearly as 

 salt as the sea, and though searched for repeatedly the plant has not 

 been found there since. Ch. aspera, then found in company with 

 C/i. crinita (as it frequently is), has disappeared also from that pond, 

 though it may still be found in Fort Pond, a few miles distant, asso- 

 ciated with Ch. delicafiila^ K'g. Forma leptosperma has been found at 

 Polpis, Nantucket, by Mrs, Maria L. Owen. In the brackish lakes 

 of Western Canada Prof. ]\Iacoun gathered, along w^ith Ch. evoluta, 

 some plants which approach very closely to Ch, criniia. They seem 

 to be dioecious (no antheridia could be discovered), and to lack the 

 small bracteoles in front of the sporangia, and they have large nuclei. 

 Prof. Nordstedt writes that Ch. crinita exhibits, in rare specimens, 

 some tendency to the development of secondary cortex-tubes. 



Chara evoluta, Allen {in lit, ad Prof. Nordstedt, 1881).— ^2/- 

 chara^ diplostephana, haplosticha (vel sub-diplosticha), nwnica. 



Humilis, 1 — 15 centimm. alt. Caulis aculeolis numerosis arma- 

 tus, haplostiche vel sub-diplostiche corticatus ; aculeolis binis fascicu- 

 latis, caulis diametrum aequantibus. Folia verticilli 9 — 10, plerumque 

 9, haplostiche corticata ; articulis 4 — 5 (saepissime 5) corticatis, ul- 

 timo nudo bi-cellulari; articulis fructificationem gerentibus 3 — 4. 

 Foliola omnium geniculorum evoluta, verticillata, sporangio longiora, 



