27 



I have used the old name of Velley while Collins has 

 preferred that of Decaisne because, as he writes, there is a ques- 

 tion whether the European plant is the same as Conferva um- 

 bilicata Veil, from the Hawaian Islands. Should such a differ- 

 ence prove to be present on an examination of the original speci- 

 men of Velley then of course we have to give our plant another 

 name. Judging from the very good figure in Velley's paper 

 I am most inclined to consider his plant as being like ours, this 

 most probably being an old type distributed in all warm seas. 



The chromatophores are small polygonal plates and form 

 by means of their prolonged corners a rather open network. Each 

 chromatophore contains a large pyrenoid. Below the chromato- 

 phores several nuclei occur distributed rather regularly. 



The cell division seems to take place in a similar way as 

 in Anadyomene, also in this form I have never found the cell 

 contents divided in parts or balls. 



Lat. fd. crassior. = ca. 160 «. 

 Lat. fd. tenuior, = ca. 60 ,«. 



This species occurred in rather deep water only, 20 — 40 

 meters, where it was found growing on stones or shells or epi- 

 phytic on larger alga?. 



I have only found it in open sea: SL. Thomas in the sea to the 

 west of Water Island; St. Jan in the Sound between this island and St. 

 Thomas off Cruz Bay in several places. 



Geogr. Distrib. Seems to be widely distributed in the warmer seas. 



Subfam. 2. Valoniece. 

 Valonia Ginn, 



1. Valonia ventricosa J. Ag. 



J. Agardh, Till Algernes Systematik, .5te Afdeln., VIII. Siphonese, 

 1886, p. 96. ViCKERS, Phycologia Barbadensis, p. 21, pi. XXIII A. Borge- 

 SEN, in Botanisk Tidsskrih, 32. Bind, 1912, p. 241. 



This species described from specimens from St. Croix col- 

 lected by 0RSTED was already found there in the beginning of 

 the nineteenth century by West, who called the plant Ulva 

 vesicaria. Beautiful specimens collected by him are found in 

 Vahl's Herbarium in the Botanical Museum, Copenhagen, but 

 so far as I know no description of the species from that time 

 was published. 



In »Hydrophytologia Danica«, Lyngbye p. 72 mentions 



