New Genera and Species of Diatomacem. By M. P. Petit. 243 
puncta irregularly disposed, and giving the valves a rugose 
appearance. Length 132 //,. 
Campbell Island (rare). PI. XV., Fig. 17. 
[This form belongs to my genus Perrya. — F. K.] 
SuRIRELLA, Ehr. 
15. S. Filliolii (P. Petit). Valves elliptical ; margin contract ; 
extremities largely rounded ; costae dilated towards the margin, not 
reaching to the centre ; each of these has two or three firmly 
punctate striae of the same length as itself. Midway between the 
summits and the centre are two short parallel punctate lines {vers 
le centre se trouvent deux lignes punctuees et atropliiees). Length 
108 to 126 jji, breadth 42 to 54 
Foveaux Strait. PI. XV., Fig. 18. 
This beautiful species (dedicated to M. le Dr. H. Filhol) is allied 
to 8. arabica, Grim., in Schmidt’s ‘ Atlas,’ pi. xx. fig. 5 ; but it does 
not possess the uncontracted second margin of that species ; its 
costae are also more distant. Its place is between S.fastuosa and 
S. arabica. 
Trachysphenia,* P. Petit. 
This genus by its cuneiform valves establishes its connection 
between the Fragilarias and Meridion. The frustules, as seen in 
f. V., are quadrangular. The cuneiform valves are covered with 
puncta disposed in vertical and horizontal lines at right angles to 
each other. The costae of Plagiogramma do not exist here. 
16. T. australis, P. Petit. Characters same as genus. 
Length 35 to 52 /x, breadth 8 to 11 //-. 
Lyell’s Bay ; Campbell Island. PI. XV., Fig, 19. 
[The valves can scarcely be called cuneiform ; they are elliptic- 
lanceolate, and the ends are usually symmetrical. O’Meara refers 
a similar form to the genus Terebraria, of Greville {T. Kergue- 
lensis, ‘Linn. Soc. Jour.,’ vol. xx. p. 56, pi. i. fig. 4). It is 
perhaps identical with Fragilaria pinnatula, Ehr., ‘ Mik.,’ 
pi. XXXV. A, xxii. fig. 8. T. australis differs from T. Kerguelensis 
by its larger granules and the blank spaces at the apices. — F. K.] 
Grammatophora. 
17. G. longissima (P. Petit). Frustular view narrow; un- 
dulations of the villi nearly reaching the centre ; number of 
undulations 25. Length 114 /x, breadth 8 //, 8. 
Lyell’s Bay (rare). PI. XV., Fig. 21. 
This curious species is distinguished from G. serpentina by the 
narrowness of the valves, and the extremities of the undulation 
lipaxvs, rough ; and '2,(pw, a wedge. 
