294 Mr. 0. Mereschkowsky 071 CaU/orni'an Diatonift. 



in the fig. 24 of Plate IV. The ra|)lie is to be seen as a crack 

 in the wall of tlic fiustule, and tlie areas are deep invagina- 

 tions of the surface of the valve on both sides of the raphe. 



22. Navicula forcipata, var. nummularia, Grev. Calif, guano. 

 [C] 



23. Navicula (Rhoiconeis) garkeana, Gr. California, North 

 Pacific. [C] 



24. Navicula ( Rhoiconeis) genuflexa, Kiitz. San Pedro, 

 rather common. [M-] 



The endochrome is composed of two chromatophore-plates, 

 with a deep and narrow sinus on each side in the middle of 

 the plates, and usually two, sometimes more, elseoplasts 

 (PI. IV. fig. 25). 



25. Navicula granulata, Bail. {Navicula Bailei/ana, Gr.). 

 Calif, guano ; North California, rare. [C, M.] 



•26. Navicula (Libellus) Grevillei, Ag. [C] 



27. Navicula (Libellus) hamulifera^ Grun.? San Pedro. [M.] 



2b. Navicula Hennedyi, W. Sm. [C] 



29. Navicula Heunedyij var. californica, Grev. [C] 



oO. Navicula Hennedyi, var. circumsecta, Grun. [C] 



It is on account of its synonym Nav. caliform'ca, A. S., 

 that 1 have placed this species in the list of Californian 

 Diatoms, although Cleve does not mention it in Ills ' Synopsis ' 

 as belonging to this locality. 



81. Navicula irrorata, Grev. Calif, guano. [C] 



32. Navicula libellus, Greg. Santa Monica, amongst Macro- 



cysti's, not very common. [M.] 

 Length 0*084 mm. Endochrome composed of two chroma- 

 tophore-plates of the same shape and disposition as in 

 N. complanata *, but the inner angles of the plates are united 

 by a loop or narrow band crossing the interior of the cell, so 

 that in reality there is but one plate. I am very much in- 

 clined to think that such a connecting band exists also in 

 N. complanata. 



33. Navicula lyra, var. dilatata, A. S. San Pedro. Rare. 



[M.] 



34. Navicula lyra, var. recta, Grev. Calif, guano. [C] 



35. Navicula (Schyzonema) mollis, \V. Sm. San Pedro, 



rather common. [M.] 



* Cleve, ' Synopsis of the Naviculoid Diatoms,' part i. p. 153. 



