486 CLEVE, DIATOMS. 
17. Isthmiez2. 
Isthmia enervis: Ehb. (W. Sm. Syn. II, påg. 52, Pl. XLVII) 
Finm. 
I nervosa Kätz. (W. Sm. Syn. IT, pag. 52, Pl. XLVII) Bee- 
ren Id, Iceland, Finm., Spitsb. 
18. Eucampiez. 
Pucampia Payeri Grun. Mpt. — F. J. L. 
19.  Rhizosoleniez2. 
Rlvizosolenia styliformis Btw (Van Heurck Syn. Pl. LXXVIII, 
fig. 5) Greenl. (Davis Strait), Northern - Atlantic Ocean, 
Finm., Kara. 
R. setigera Btw. (Van Heurck Syn. Pl. LXXVIII, fig. 6—28) 
Northern Atlantic Ocean, Cape Wankarema. 
BR. alata Btw. (M5 J., VI, page. 95; Pl Vufgd8) Greenl. 
(Tindingen), Northern Atlantic. 
R. Shrubsolit Ci. (Van Heurck Syn. Pl. LXXIX fig. SE) 
Northern Atlantic. 
R. hebeta Bail (Brightw. M. J. VI, P1. V, fig. 4) Cape Wan- 
karema. F. J. L., Behring Sea. 
The only figure given of this species is very imperfect, for 
which reason I bave given another. Pl. 38, fig. 69. — Length 
of frustle 0,5 Breadth 0,03 mm. Strie punctate, 25 in 0,01 on 
the connecting membrane, crossing each other in three direc- 
tions. 
Pyzxilla? baltica Grun. (A. Schm. N. Sea. Diat. P1. III, fig. 25. 
Van Heurck Syn. Pl. LXXXIII, fig. 1—2) Cape Wankarema. 
Pyzxilla? variabilis Grun. (Van Heurck Syn. LXXXIII, fig. 
3—4) »Arctic Ocean». 
20. Chetocere2. 
Cheetoceros decipiens Ol. (D. of the A. Sea pag. 11, P1. I, fig. 5) 
Greenl. (Davis Strait, Tindingen) Northern Atlantic. 
var. conereta Grun. (A. Diat. pag. 120) together with the 
genuine form. 
