6 CLEVE, DIATOMS FROM THE WEST INDIAN ARCHIPELAGO. 
39. N. St. Thome CL. N. Sp. Two times and a half longer 
than broad, ends produced. Outline wundulate. Strig 
very coarse, radiate, 3—6 or 0,01 m.m., marginal, leaving 
a broad area around the median line. DL. 0,061 m.m. 
Br. 0,0255 m.m. Fig. 4. ££2. — Of this form, according 
to Mr. GRUNOW allied to his N. Botteriana, only one spe- 
cimen from Virgin Ids has been seen. 
40. N. (distans var.) pennata (N. pennata A. ScHym. Atl. 
P1. 48 fig. 41—43). St. Bartholomew. 
41. N. longa GREG. (??) A. Scem. (Atl. Pl. 47 fig. 6) Virgin 
Ids. rare. 
42. N. direceta W. Sm. (A. Scem. Atl. Pl. 47 fig. 5) St. Bar- 
tholomew. 
43.0 N.sp. AScHM. (Atll Pl 148: fig.::90) Virgm Idsbvare: 
44. N. (?) Bartholomei. CL. N. Sp. This beautiful form may 
perhaps be N. Perryana Kitton (Trans. Micr. Soc. 1873), 
of which no figure has been published and with which the 
indentification consequently is impossible. It belongs to 
the same section as N. Jamaicensis, N. strangulata etc., 
which are to be broken out as a separate genus from 
Navicula. Mr. A. ScHmipT calls this group Pseudodiplo- 
neis (Nordseediat. pag. 87). Most of these forms are 
more allied to Mastogloia than to Navicula. The N. Bar- 
tholomei is strongly constricted in the middle; its ends 
are cuneate as on allied forms. Sculpture: large and strong 
parallel coste, reaching neither the margin nor the median 
line, abbreviate around the central nodule. The margin 
has a row of small granules. &L. 0,075 m.m. Fig. 5. 222. 
Another to the same section belonging species is N. for- 
micina GRUN. in litt., of which he gives the following discrip- 
tion: >Valve composed of two rhombic halves, connected by a 
very narrow isthmus, which is slightly enlarged in the middle. 
Strie parallel, not reaching the median line and wanting in 
the middle of the valve, very delicately punctate, 6 in 0,01 
mim. du. 0;057- mm. IB. of the lobes; 0,072tmamn. for the 
isthmus: 0,004—0,005 m.m. — Hab. Campeche Bay (commu- 
nic. by Dr. GRUNDLER). — Fig. 6. 22. 
45. N. aspera E. (Stauroneis pulchella W. Sm.) Virgin Ids. 
common. 
46. N. Goesii C1. N. Sp. HElliptic, with produced and sub- 
capitate ends. Strie distinct, 14 on 0,01 m. m., parallel, 
