110 
— Closterium Libellula was identified by me 1888 
with Feniiim closterioides. When this species is kept 
in Closterium^ as Lütkemüller does, the species name 
Libellula ought to be kept also. — dost Lina is 
perhaps identical with CL directîcm Arch. 1862, as 
some authors believe, but it seems to me not quite 
sure. — CL Ensis is now looked upon as CL didy- 
motocum Ralfs 1848 (in my opinion not Corda in 
Aim. Oarlsb. 1835). 
2. Kützing’s Tab. Phycol. 1, 1847: Entospiror 
closteridia Bréb. in litt, was regarded by Archer 
1864 as a Spirotcenia. Lütkemüller says in Osterr. 
bot. Zeit. 1903: ”Kützings Definition ist unzureichend, 
in seiner Figur erscheinen die Zellen weniger schlank 
und mit schmälerem Chlorophyllband als in Brébis- 
sons AquarelP. 
Now we will consider, whether any species in 
”Brit. Desm,” should have other and earlier names, 
or wether any earlier name ought to be remembered 
at the dividing of a species, which in Ralfs’ book 
contain really~more than one species. In some cases 
we will demonstrate, that a name taken up from an 
older author is very doubtful or incorrect and that 
then Ralfs ought to be quoted as author. 
jDidymoprium Grevillei. Ralfs had in 1845 kept 
Gre ville ’s species-name cylindricum from 1827, but 
in 1848 he accepted the first given combination of 
species-name with the genus Didymoprium: I). Grevillei 
Kütz. 1843. Later authors have commonly used 
Desniidium or Didym. cylindricum. 
Splicer oøosma. The printing of Alman, de Carlsbad 
1835 was finished in Dec. 1834 (separata sent round 
at least in the beginning of 1835). The introduction of 
Brebisson’s Alg. Fal. was dated ”15 avril 1835”. 
On account of that, JDesmidium vertebratum is a youn¬ 
ger name than Spheerozosma elegans.^ but as this 
