298 Mr. C. Mereschkowsky on Californian Diatoms. 
The double lyre-like figure has been reproduced by O’Meara 
in an exaggerated way; it is not nearly so distinct as in his 
figure, and is not limited by lines, but by two decussating 
rows a little more distant than the others. 
As to the diatom which has been described by Cleve * 
under this name, it belongs in all probability to another 
species, as he does not mention the lyre-like figure ; but, on 
the other hand, he mentions the existence of a double row of 
puncta between which the median line is enclosed, which 
means, I suppose, that these puncta are distinct from the rest, 
as they are, for instance, in M. (O.) barbadensis, Grev.f, 
and which is not the case in Jf. (O.) Wrightii, these puncta 
not differing from the others. ‘This would explain the 
yemark which Cleve makes at the end of his description, 
when he says, “ None of the figures (that of O'Meara in- 
clusive) corresponds exactly with this species, so that the 
identification is doubtful.’ It is evident that this author has 
had in view some other species than the original JZ. (O.) 
Wrightii of O’ Meara, or some variety of the latter. 
67. Mastogloia pumila, Grun. San Pedro, not very rare. [M.] 
68. Amphora acuta, var. arcuata, A. S. San Pedro, rare. [M.] 
Length 0°086, breadth of the frustule 0°068 mm.; zone 
with 4 longitudinal divisions in 0°01 mm. 
69. Amphora acutiuscula, Kiitz. Laguna near San Pedro, 
common. {M.] 
70. Amphora angusta (Greg.), Cl. San Pedro, rather rare. 
[M. } 
71. Amphora angusta, var. ventricosa, Greg. [C.| 
72. Amphora coffeiformis, Ag. San Pedro, common. [M.] 
73. Amphora costata, W.Sm. San Pedro, not common. [M.] 
74, Amphora hyalina, Kiitz. San Pedro, rare. [M.] 
75. Amphora lineolata, Ehr. San Pedro, common. (Cy, Nes 
76. Amphora marina, W. Sm. Monterey, rare. [ M. 
77. Amphora ostrearia, Bréb. San Pedro, common. [M. | 
78. Amphora proteus, Greg. Northern Calitornia, rare. [ M.] 
79. Amphiprora alata, Kiitz. Santa Monica, brackish, very 
common. [C., M.] 
Endrochrome composed of two plates disposed transversely, 
leaving in the centre a circular hyaline space. 
80. Amphiprora paludosa, W. Sm. San Pedro. [M.] 
* Cleve, ‘Synopsis of the Naviculoid Diatoms,’ part ii. p. 148. 
+ ©Diatomeentafeln zusamm. f. ein. Fr.’ pl. ly. fig. 10. 
