SYSTEMATIC HISTOHY OF THE INFrSORTA. 



of frastiile 1-84" to 1-72". The charac- 

 ters given are insufficient to distinguish 

 this species from L. splendida. 



L. divisa (K.). — Frustules elongate 

 cuneate, subsolitary or geminate (not 



flabellate), acute at the base ; stipes 

 short, weak, subdi\aded. KSA. p. 114. 

 Adriatic Sea. (xiii. 16.) Length of 

 frustule 1-240" to 1-180". 



Genus CLIMACOSPHENIA (Ehr.). — Frustules in front view cuneate, 

 ■with moniliform longitudinal \itt8e, laterally obovate-lanceolate, divided into 

 chambers by transverse septa. Marine. This genera resembles Podosphenia, 

 except in having the peculiar transverse septa. ^' The two (first) species 

 contained in this genus have nothing in common except the moniliform vittae. 

 But in what these really consist we cannot ascertain from the figures. In 

 the first Kiitzing does not delineate the lateral surfaces, and from the figure 

 any one would say that he had drawn a Synedra. The second, again, 

 resembles a Podosphenia." (Meneg 7. c. p. 465.)] 



Clumacosphenia AustraKs (K.). — 

 Very shortlv stallved, with smooth mar- 

 gins. KB.llO. f.8. OnAlgaj. New 

 HoUand and Southern Afi-ica. 



C. momlif/ern (E,). — Frustules trans- 

 versely striated on the margin; septa 

 10 to 11 in number. IvB. t. 29. f. 80. 

 Cuba, Mexico, (xi. 45, 46.) 



C. elonfjata (B.). — Lateral view elon- 

 gated clavate, the intercostal spaces with 

 obsolete transverse striae ; stipes long, 

 branched. BC. 1853, p. 8, pi. 1. f. 10, 

 11. Florida. Professor Bailey relies 



on the " elongated-clavate fonn of the 

 frustiUes and their excessively minute 

 striations, to distinguish this species 

 from those previously described by Ehr- 

 enberg and Kiitzing. The strife can be 

 made out without much difficidty near 

 the edges ; but to trace them completely 

 across the middle regions of the valve 

 requires excellent lenses and careful 

 management of the light." (Bailey.) 

 Frustides in fan-shaped gToups, narrow, 

 linear-cuneate, with conspicuous moni- 

 liform longitudinal vittae. 



Genus PODOCYSTIS (K. &Bail.)=EUPHYLLODIUM (Sh.).— Frustules 

 stipitate, cuneate in front view with obscure vittae ; valves with transverse 

 costae, moniliform striae, and longitudinal median line. Podocystis differs 

 from Siuirella not only in its stipitate frustules, but in its moniliform striae 

 and absence of alae ; and from Bhaphoneis by its cuneate frustules. We 

 have placed it with the Licmophoreae because of its resemblance to Podo- 

 sphenia, notwithstanding its obscure vittae and strong transverse costae. 

 Maiine. 



Podocystis Adriatica (K.). — ^\^alves 

 ovate, with 11 or 12 sti^ae in 1-1200", 

 stipes veiT short. = fiurirelJa (Pudocystis) 

 Adriatica, KB. p. 62, t. 7. f 8 ; P. Ame- 

 ricana, BMO. pi. 11. f. 38 ; SB. ii. p. 101 : 



JEuphyllodiimi spathidatum, Shadb. MT. 

 ii. p. 11, pi. 4. f 4 ; Dorypliora ? elegans, 

 Roper, MJ. ii. p. 284. f 3. Europe, Afi-ica, 

 and America, (iy. 10.) 



Genus SCEPTBONEIS (E.).— Frustules simple, affixed, cuneate, com- 

 pressed, styliform ; in the lateral ^dew with moniliform transverse striae, 

 interrupted by a median longitudinal suture. Marine. Sceptroneis has the 

 habit of a nonconcatenate Meridion and of a Gomphonema without the 

 central nodule of the lateral valves. 



Sceptroneis Caduceus (E.). — Frus- 

 tides bacillar, long, slender, inflated at 

 centre and upper end, and tapering below. 

 BAJ. xlviii. pi. 4. f. 11. Fossil, Ame- 

 rica ; recent, Scotland. The lateral view, 



the only one we have seen, is narrow, j in Scotland, (iv. 11.) 

 somewhat clavate, constricted beneath i 



the head, which is rounded at its apex. 

 Transverse striae with pear-like gra- 

 nules. Length 1-92", exceeding the 

 width about 18 times. Professor Gre- 

 gory gathered a fragment of this species 



