510 CLE V E,^ I) I A TO 31 S. 



u 



A. quaternatus Elib. (Jan. Guan PI. I, A., fig. 8). 



.4. splendens (Shadb.) Ralfs (Halionyx undenarius Jan. Guan. 

 PI. I, fig. 1). 



''' Aster oniphaJ us flcibellatus Breb. (Grev. M. J. VII, p. 160, 

 PL VII, fig. 4 et 5). ' 



Melosira sulcata Ehb. 



M. (Endictya) oceanica Btw. (A. S. Atl. PI. LXV, fig. 10, 12, 13). 



* Fodosira Argus Grnn. (M. J. 1879, PL XXI, fig. 6). Dia- 

 meter 0,08 mm. Stricie on the rim about 20 in 0,oi mm. The 

 puncta which compose these stria3 are arranged in quincunx 

 as iu many species of Pleurosigma. 



P. mactdata W. Sm. (Lagerst. Bih. t. K. Sv. Vet. Ak. HandL 

 HI, No 15, fig. 1). 



. '' P. Montagnei Kiltz. (Van Ileurck Syn. PL LXXXIV, fig. 11). 



* P. amhigua Grun. (A. D. p. 118, M. J. 1879, PL XXI, fig. 7). 

 '•' P. maxima (Klitz.) Grun. (A. D. p. 118). Diam. 0,o65 mm. 



Umbilic. O.oi min. Rows of puncta IG in 0,oi mm. near the 

 umbihcus, 20 near the margin. 



VI. Diatoms from Bab-el-Mandeb. 



Between Aden and Bab-eLMandeb were taken samples of 

 bottom-mud, which contained, sparsely, some diatoms, among 

 which I have determined the following: 



AmpJiora sebrina Jan (A. Schm. Atl. PL XXV, fig. 11). 



A. rohusta Greg. (Diat. of CI. pag. 516, PL XIII, fig. 79). 



A. Froteus Greg. var. 



A. crassa Greg. (Diat. of CI. pag. 525, PL XIV, fig. 94). 



A. furcata Leuduger-Fortm. (Diat. de Ceylan pag. 20, PL 



I, fig. 11). 



A. mexicana A. Schm. (Atl. PL XXVII, fig. 47—48). 



A. cymblfera Greg. — Length of valve 0,o85 mm., breadth 

 0,011. Stride 8 in 0,oi mm. composed of distinct granules. 



Navicula aspera Ehb. 



N. directa W. Sm. — Length 0,ii mm. Breadth 0,oi3 mm. 

 Stria? 6 in 0,oi mm. 



JV. maxima Greg. var. BJelschil Jan (A. Schm. Atl. PL L, 

 fig. 22 — 25) Length 0,i3 mm. Stride 17 in 0,oi mm. 



N. maxima Greg. var. umhilicata Grun. (A. Schm. Atl. PL 

 L, fig. 32 — 33) Length 0,i3 mm. Stria3 12 in 0,oi mm. in the 

 middle, 15 in 0,oi mm. near the ends. 



