Mr. C. Mereschkowsky on Californian Diatoms. 519 
EXPLANATION OF THE PLATES. 
PrarE LV: 
Fig. 1. Nitzschiella tenuirostris, Mer. (typica). San Pedro. -. 
Fig. 2. Ditto. a, valve; 0, girdle-face. San Pedro. ae 
Fug. 3. Ditto. San Pedro. ”. 
4,5. WN. tenuirostris, forma directa. San Pedro. se 
Tr 
Tig. 6, N. tenuirostris, var. hamulifera, Mer. Mediterranean (Ville- 
300 
franche). > 
Fig. 7. Ditto. Diagram showing the spiral torsion of the ends. 
Fiy. 8, N. tenuirostris, var. parva, Mer. Valve. Black Sea (Theo- 
. . () 
dosia, Crimea). = 
Fig. 9. Ditto. Girdle-face of the same individual. 
Fig. 10. Ditto. San Pedro, °. 
Fig. 11. N. tenucrostris, forma minutissima. San Pedro. ae 
Fig. 12. Nitzschiella gracilis, Mer. (typica). Valve. San Pedro. a 
Fig. 13. Ditto. Girdle-face of the same individual. 
1g. 14. N. gracilis, var. reversa, Mer. San Pedro. .. 
Figs. 15-17. Nitzschiella biplacata, var. pacifica, Mer. Figs. 15 & 17, 
valves ; fig. 16, girdle-face. San Pedro. ~~ 
Figs. 18-20. Nitzschiella californica, Mer. Fig. 18, valve; figs. 19 & 20, 
girdle-faces. Redondo, California, 
Fig. 21. Cylindrotheca gracilis (Bréb.), Grun. San Pedro. = 
Figs. 22, 23. Mastoglova (Orthoneis) Wrightii, O'Meara. Northern Cali- 
: 00 
fornia. STi 
Fig. 24. Optical section through a frustule of Navicula forcipata, 
Grey. = : 
Fig. 25. Navicula (Rhoiconeis) genuflera, Kiitz., with cell-contents, San 
Pedro. 
Fig. 26. Diploneis papula, A. S., with cell-contents. San Pedro. 
Fg. 27. Biddulphia (Triceratium) sanpedroana, Mer. San Pedro. “ 
Figs. 28-80. Biddulphia simplex, Mer. San Pedro. Figs. 28 & 29 - : 
PuaTE V. 
Figs. 1-8. Liemophora lata, Mer. San Pedro. * 
Figs. 4, 5. Licmophora pacifica, Mer. In fig. 4 the striz are not repre- 
600 
sented. San Pedro. —. 
: : 600 
Fig. 6. Licmophora montereyana, Mer, Monterey. —-. 
Fig. 7. Licmophora Thumii, Mer. Monterey. se: 
Figs. 8, 9. Liemophora Monks, Mer. San Pedro, ae 
