OF THE SUEIEELLEiE. 



795 



1-1152". EM. pi. 33. 12. f. 27. Fossil. 

 Oregon. A specimen 1-336" long pre- 

 sented 19 strise. Ehrenberg's figiu'e is 

 elliptic-lanceolate, witli a median line 

 dilated at the centre into a large oval 

 form ; the striae short and externally ter- 

 minating in gland-like dots. 



S. turgicla (S.). — Elliptic-lanceolate, 

 with tapering, sometimes contracted 

 ends and obtuse apices ; costse few (4 in 

 •001"), conspicuous, separated by a me- 

 dian lanceolate space. SBD. i. p. 31, 

 pi. 8. f. 59. = >S'. Caledonica, EM. pi. 15 a. 

 f. 47 ? Aquatic. Ireland. Distinguished 

 by its ventricose centre. 



S. ohlonc/a (E.). — Oblong-lanceolate, 

 with obtuse ends, near the margin si- 

 nuoso-dentate. KSA. p. 35. Aquatic. 

 Africa; America; Mourne deposit, Ire- 

 land. Ehrenberg's figures in the ^ Micro- 

 geologie' difier very much in form, but 

 all have the costEe confined to the 

 margin. 



S. Breuteliana (Rab.). — Linear-elliptic, 

 with rounded ends, five transverse costae 

 on each side, connected at inner ends by 

 an imdidated line, and leaving a longi- 

 tudinal median space with waved mar- 

 gins. Rab D. p. 29. t. 3. f.13. Aquatic. 

 St. Kitts. 



S. crenulata (E.). — Small, elliptic-lan- 

 ceolate, with crenulate margins, subacute, 

 nearly equal ends, and a distinct median 

 line; eleven crenides in 1-1152", extend- 

 ing into striae, which do not reach the 

 centre. EM. pi. 33. f. 23. Fossil, United 

 States. D. 1080". 



%. microcora (E.). — Minute, oblong- 

 lanceolate, with somewhat acute apices, 

 and marked near the margin with ten 

 delicate dentations in 1-1200". EA. 

 p. 136, t. 2. 1. f. 34; KB. t. 29. f. 15. 

 Asia, Africa, America. 



S. lepida (E.). — Slender, linear-lan- 

 ceolate, one end obtuse, the other a little 

 more attenuated and subacute ; striae nine 

 or ten in 1-1152" j the median line di- 

 stinctly flexuose. ERBA. 1844, p. 272 ; 

 KSA. p. 36. Km-distan. 1-768". 



S. tenella (K.). — Oblong-lanceolate, 

 with rounded, obtuse apices, and five, 

 rather lax transverse striae in 1-1200"; 

 front view oblong, almost rectangular, 

 with obtuse angles. KSA. p. 37. Aquatic. 

 Prussia. 



S. ohtusangula (Rab.). — Small, lan- 

 ceolate, with cuneate, attenuated, obtuse 

 ends, and six short costae in 1-1200"; 

 front view oblong, broadlv roimded. Rab. 

 p. 29, pi. 3. f 27. Aquatic. Germany. 



»S. Aniphioxys (S.). — Elliptic-lanceo- 

 late, with subacute extremities, and nine 



costae in -001"; front view Imear. SBD. 

 ii. p. 88. Haverfordwest. 



S. angusta (K.). — Minute, linear, with 

 cuneate ends, rather obtuse apices, and 

 11 costae in 1-1200" ; alae obsolete ; front 

 view linear, trimcate. KB. t. 30. f. 52 ; 

 SBD. pi. 31. f. 260. Aquatic. Europe ; 

 Lewes. 



S. apiculata (S.). — "Elliptical, ovate, 

 smaller extremity produced into a linear, 

 truncate apiculum; costae 15 in -001"." 

 SBD. ii. p. 88. Aquatic. England. 

 Length of frustule -0008" to -0012". " A 

 close ally, if not a variety, of S. angiista." 



S. linearis (S.). — Minute, linear, with 

 cuneate ends, distinct transverse costae, 

 and a narrow median line. SBD. i. pi. 8. 

 f. 58=^'. = S. acuminata (Breb. MS.). 

 Aquatic. England, France. Var. /S, 

 slightly constricted at the middle, S. 

 p. 8. f. 58^". In the front view this 

 species resembles a small form of S. 

 hiseriata. 



3* Lateral view with one end broadly 

 rounded, the other smaller (ovate or 

 ovate-ohlong) ; front vieiv usually cu- 

 neate. 



S. rohusta (E.). — Large, elongated; 

 ovate-oblong, with two stout costas 

 (which do not reach the centre) in 

 1-1200". EM. pi. 15 A. f. 43. S. nohilis, 

 SBD. pi. 8. f 63. Aquatic. Fossil. Fin- 

 land; Britain. 1-216" to 1-120". Di- 

 stinguished by its large size, elongated, 

 slightly tapering form, and large intra- 

 marginal crenations. 



S. procera, EM. pi. 14. f. 33. Berlin. 

 The figure represents a large species, 

 slightly broader at one end, with large 

 intramarginal crenations as in S. rohusta^ 

 but the strong transverse costae are sepa- 

 rated only by a narrow median band. 



S. splendida (E., K.). — Front view 

 cuneate, with rounded angles and pro- 

 longed costae ; lateral view ovate-oblong 

 with conspicuous, diverging costae which 

 reach the median line ; alae distinct. 

 EM. t. 15 a. f. 44; SBD. i. pi. 8. f. 62. 

 Aquatic. Common, both living and fossil, 

 (ix. 150-152.) Var. ^. linearis, smaUer, 

 lateral view narrow, slightlv tapering, = 

 S. Unearis, SBD. i. pi. 8. f. 58 a. 1-210" 

 to 1-100". As the front view has rounded 

 angles, it is not unlike the lateral one in 

 outline, but the ends are broader. Two 

 or three times as long as broad. 



S. tenera (Greg.). — Narrow linear- 

 oblong, with one end more tapering than 

 the other; costae distinct, reaching the 

 median line. Greg MJ. iv. p. 10, pi. 1. 

 f. 38. Scotland. It is smaller than ^S". 



