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NOVAE A DIATOMS. 



Descriptions of New Genera and Species of Diatoms obtained by the 

 Austrian Imperial Frigate Novara, during her Voyage round 

 the World. 



By Herr A. Grunow. 



(Translated by F. Kitton.) 



Part II. 



Schizonema reptabundum, Grun. — Frond minute, tubes minute, 

 thin, creeping on various Alga?, navicular generally in simple series, 

 frustule broad at the ends, centre slightly attenuated, valve narrow, 

 rhomboido-lanceolate, apices somewhat obtuse, central nodule large, 

 round, strito-punctate, delicate, 60 in. -001, slightly radiant, more 

 conspicuous near the centre. PI. v, fig. 1, a portion of a tubule, 

 with the frustules included, b c valves. 



Upon Calithamnium Borreri, from the coast of Madeira, Jelinek ; 

 from Dalmatia, Dr. Lorenz. 



This small, but characteristic species, has been long known to me 

 as frequently occurring on C. Borreri, obtained from various 

 localities. 



The valves bear boiling in nitric acid very well. 

 Striatella chilensis, Grun. — Minute frustules, quadrate, longer or 

 shorter than broad, septa?, (dissepimentis) imperfect, more or less 

 numerous, arcuate; valves broad, linear, apices rounded, sides 

 slightly orbicular, stria? delicate, parallel, 50-55 in. *001 ; median 

 line distinct in the large valves, obsolete in the small valves. PI. 

 i, fig. 2, a and d valves, b narrow frustule, c broad frustule. 

 Upon Algae, from Valparaiso. 



Approaches my S. kamtschatica very nearly, but differs from it 

 in its smaller form, delicate stria?, and especially by its constantly 

 arcuate septa?, which are many times repeated and cut through, and 

 overlie the conspicuously convex central line, something after the 

 manner I have figured my Euodia Frauenfaldii. 



Fxagillaxia (?) Nankoorenis, Grun. — Valves linear, lanceolate, 

 constricted below the apices, which are round, subcapitate, and pro- 

 duced ; median line and terminal nodules distinct, stria? transverse, 

 not punctate, 17 in. -001, absent from the centre and below the 

 apices. PI. v, fig. 3. 



Very rare in the " Polycystin stone," from Nankoori. 

 Of the form of Denticula fulva, Greg, but differs materially in 

 the strong costa?-like non-punctate stria?, which are interrupted by 

 a narrow smooth space at the centre. It also resembles F. am- 

 phiceros, but Ehrenberg has not figured his form with the central 

 smooth space. 



Plagiogramma stipitatum, Grunow. — A variety distinguished by 

 the peculiarity of the central costa?, which are frequently inter- 



