New Diatoms f rom Honduras. Described by A. Grunow. 169 
nearly related to Diatoma, Odontidium, &c. I had employed the 
name of Staurosira as a sub-genus of Fragilaria, but both genera 
must be separated and even placed in different families. To 
Staurosira belongs the greater part of Fragilaria, and it would 
perhaps be better to retain the name of Fragilaria for it, but then 
a new name would be necessary for Fragilaria virescens, a thing 
to be avoided if possible. 
Sceptroneis. 
Sceptroneis cuneata Grun. (Synedra cuneata Grun. in Hed- 
wigia, l. c.). S. valvis elongatis clavatis in apice cuneatis, obtusis, 
linea media nulla (vel indistincta), sulcis duabus longitudinalibus 
margin approximate aut distinctissimus aut obsoletis, interdum vix 
conspicuis, striis transversis (12-13 in 1 01 mm.) subtiliter 
punctatis (punctis lineas longitudinales densas efficientibus). Longit. 
•21-’ 32 mm., latit. valvae • 018- '024 mm. Tab. CXC1V., 
Fig. 3, a, b, c, d. 
Common in the Honduras gathering. 
S. cuneata is nearly related to Synedra clavata Greville 
[‘ Trans. Mic. Soc.,’ vol. xiii. p. 25, Greville notices the resemblance 
of bis form to S. robusta, Kalfs, and I have seen the latter species 
as distinctly cuneate as S. clavata. — F. K.], and S. Gomphonema 
Janiscb et Eabenborst, but differs from both of them by the absence 
of a distinct median line. S. clavata has much coarser striae (6 in 
• 01 mm.) and a greater breadth ( • 038 mm.). [In a paper by Otto 
Witt, in the Journal of the Godeffroy Museum, Part I., a form 
resembling S. cuneata is described and figured under the name of 
Synedra clava, O. W. I have a similar species from Colon. — F. K.] 
Synedra Gomphonema is known to me only by the delineation, 
which shows a broad median line. The striae are described as fine, 
which cannot be said of Sceptroneis cuneata. I have seen another 
form (but only once) in the Honduras gathering. This is 
S. dubia, Grun. S. valvis clavatis, basi rotundatis, apice paullum 
producto, obtusiusculo, linea media distincta, sulcis marginalibus 
nullis, striis subtiliter punctatis (10^-11^ in • 01 mm.) in basi 
radiantibus, in apice subradian tibus. Longit. '116 mm., latit. valvae 
• 015 mm. Tab. CXCIV., Fig. 4, a, b. 
Very rare in the Honduras gathering. 
Is this an abnormal form of Synedra crystallina ? I am not 
inclined to think so, the striation on the ends of the valve being so 
very different. 
In a slide of diatoms found in stomachs of Holotburise from 
Java, communicated by Herr Weissflog, I have seen a variety of 
S. cuneata with a more slender outline and coarser strife (8 in 
•01 mm.) and no submarginal furrows; this form I have named 
S. cuneata var. Javanica. Length • 4 mm., breadth below 
