289 



fathoms Dr. Boeke brought home from St. Eustatius the 

 upper part of a Delesseria-like alga, that I could recognize 

 on comparison with material collected by the Siboga-Expe- 

 dition for a member of the genus Zellera. This genus bas 

 been described by von Martens in „Die Tange der Preu- 

 sischen Expédition nach Ost-Asien pi. VIII, but his figure 

 is an unhappy one as Mrs. Weber could ascertain, who 

 compared her spécimens from the Siboga-Expedition with 

 the authentical pièce of von Martens at the muséum in 

 Berlin. Neither is the description of Schmitz in Engler u. 

 Prantl fig. 416 entirely accurate. Zellera tawallina is 

 characterized by a curved, winged main stem, that carries 

 unilatéral and dorsal branches of second order and thèse 

 again carry leaflets, but none of thèse leaflets fasten them- 

 selves to other branches, they remain free, as I could 

 ascertain on varions Siboga-specimens. The leaflets often 

 overlap the preceding branches and in that case the plant 

 looks as if it consisted of a net-like tissue, but in reality 

 the leaflets remain free. 



The Zellera of St. Eustatius has essentially the same 

 ramification as Zellera tawallina; ail the branches issue 

 unilaterally and always from the dorsal side of the prece- 

 ding branch. It dififers from. Z. tawallina by the broader 

 wing with entire margin (fig. 2. 3.) and the pitcher-like 

 cystocarps. Z. tawallina has a narrower dentate wing and 

 globular cystocarps. I hâve only a fragment of the Zellera 

 of St. Eustatius, the dredge having only brought up the 

 top of a single plant, but the ramification is so typical 

 that I was able to recognize the genus and to describe 

 this new species for which I propose the name of Boekei 

 in honour of Dr. Boeke, who discovered the plant. — 



Sphaerococcaceae. 



Gracilaria Uchendides, L. till now only known from 



East-India. — Rif water. Cur. 



