510 Mr. C Mereschkowsky on CaUfornian Diatoms. 



160. Licinophora lata, Mer. (PI. V. figs. 1-3.) San Pedro, 

 liedondo Beacli, very common ; Monterey, common. [M.] 



Valve broad, bottle-shaped, upper part somewhat linear or 

 slightly attenuated to the summit, abruptly attenuated towards 

 the lower third or fourth, becoming conical ; lower apex some- 

 what narrow, rounded, upper broadly rounded. Pseudoraphe 

 rather broad, very distinct, stria? very fine. Girdle-face 

 moderately broad, cuneate, upper angles subrounded, upper 

 margin convex; septa very deep, 0012 mm. in average, 

 arcuate ; septal puncta distinct, round. Endochrome granular. 

 Forming numerous colonies on long stypes composed of two 

 layers, an external and a thinner but denser inner one ; mode 

 of ramification the same as in L. dalmatica, L. gracilis^ and 

 L. paradoxa. Length 0"055-0*077 mm., breadth of the 

 girdle-face 0-028-O'Oil mm., breadth of the valve 0-014- 

 0020 mm. 



This species is nearly allied to L. imradoxa^ from which it 

 difi'ers by the much broader valves of a somewhat different 

 shape ; the granules of the endochrome are rounded, while in 

 L. paradoxa they are usually elongated, bacilliform, and the 

 colonies are symmetrical, while in L. paradoxa one side of 

 the colony is always more developed than the other. 



IGl. Licmopliora Monksii, Mer. (PI. V. figs. 8, 9.) San 

 Pedro, common; Redondo Beach, not rare. [M.] 



Valve broad in the middle, slightly attenuated towards the 

 superior apex, which is truncate, sometimes broadly rounded, 

 more considerably attenuated towards the lower end, which is 

 narrow ; lower part forming an elongated cone with usually 

 straight margins. Striae fine, except at the lower end, where 

 they are distinct under an ordinary magnifying-power, about 

 12-13 in 0"01 mm. Girdle-face (fig. 9) cup-shaped, with 

 more or less convex margins, upper angles rounded. Septa 

 very deep (average 0007 mm.), very fine, almost straight 

 and parallel, somewhat divergent above the septal puncta, the 

 latter small, round, very distinct ; secondary puncta large, 

 adjoining the septa. Endochrome granular. Forming small 

 colonies on short structureless stypes. Length 0'017-0'043 

 mm. (usually 0"025-0"03.5 mm.), breadth of the girdle-face 

 0-01 2-0-021 mm., breadth of the valve 0-007-0-008 mm. 



The cup-shaped girdle-face of this species is a very peculiar 

 character, not to be found in any other species. The secondary 

 septal puncta (a, a in fig. 9), which usually are situated in- 

 wards of the septa, are here so close to the latter tiiat, if not 

 carefully examined, they can easily be mistaken for the septal 



