155 
31. Ch. robustum (Cleve) Ostf. ms.; Ch. peruvianum var. 
robustum Cleve, Diatoms from the Sea of Java, 1873, p. 8, PI. II, 
f. 8; C. boreali ? Lauder, 1. c., p. 78, f. 7. 
Denne Form synes karakteristisk og konstant nok til at være 
en egen Art. 
VIII 13 /u (rr) — IX a 15 /u (rr) — Xb 2 k (rr). 
32. Ch. rostratum Lauder, 1. c., p. 79, f. 10. 
VII a 9 /u (rr). 
33. Ch. Schmidtii Ostf. n. sp. 
Chains multicellular, frustides longer than wide (width about 
28 p), in a front view rectangular with skarp angles, valve elliptic- 
(c. 175 /l.) 
circular , hoop very long, at least 2 /s of the length of the cell, fora- 
mina broadly linear. Awns very long, rather robust, issuing from 
