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Bischoff, 1828; Pringsheim, 1862; Nordstedt, 1865; and de Bary, 
1871. Especial reference must be made to Alexander Braun, who 
illuminated every phase of the subject. The species were previ- 
ously very imperfectly understood; many of them were aggregates 
of little-related forms, but his investigations laid a firm base for all 
future work. Unfortunately, when a former species or specific name 
seemed unsatisfactory to him, he promptly discarded it, dealt sim- 
ilarly with names given by himself, and counted mere herbarium 
names and casual mention as the equivalent of publication. The 
names adopted by him are still in general use, though in many cases 
they have been departed from in this paper. More recent works 
of taxonomic importance are by Migula upon the Characeae of 
Europe; by H. and J. Groves upon those of the British Isles; and 
by Nordstedt, whose descriptions include several American forms. 
The first generic division was by Agardh in 1824, who separated 
Nitella from Chara, taking as the distinguishing character the ab- 
sence of cortex, still often, though wrongly, so considered. The real 
nature of these two genera was first shown by Braun, who at a later 
date, separated Lamprothamnus from Chara. He also made 
Tolypfella a subgenus of Vitella; this was raised to generic rank 
by von Leonhardi, in 1863, who at the same time similarly treated 
Lychnothamnus, first recognized as a section of Chara by Ruprecht 
in 1845. Chara obtusa Desv., placed subsequently in Vetella and 
Lamprothamnus, was the last of the accepted genera to receive 
recognition, which came from Hy in 1889, as Mtellopszs, and 
Migula in the succeeding year applied to it the name Zolypellop- 
szs, which, however, as a subgenus dated back to von Leonhardi 
in 1863. 
One other genus, Charopsis, to comprise uncorticated Chareae, 
was proposed by Kiitzing in 1843, with Chara Braunii as the type, 
but this character did not justify segregation, as he himself speedily 
saw. 
The first American reference to this group dates back as far as 
1696, when Sloane, in his catalogue of plants of Jamaica, identifies 
a plant from that island as the Aguzsetum foetidum sub agua 
repens of Caspar Bauhin, already mentioned. His species was 
probably C. haztensis Turpin. 
The first continental American species to be recognized was 
Chara foliolosa, sent under this name from Pennsylvania by Muhlen- 
berg and described by Willdenow. American botanists confused 
