270 Narrikal or Cochin Mad Bank. [No. 12, nbw SERIES, 



moniliform, not quite reaching the median line, a smooth median 

 fascia continued into the marginal stria? by four' unequal wedge 

 shaped space?, two on each side, stria) 21 in. 1.1000." 



Navicula— — (? Sp.) 



Broadly lanceolate, the extremities gradually contracted into 

 somewhat obtuse beaks, longitudinal stria) strongly marked, 28 to 

 1.1000," Transverse stria) rather obscure, requiring oblique illu- 

 mination, 32 to 1.1000"— length 1.120." This may be N. Indica 

 but the description* is too meagre for identification. 



Genus STATOONEIS (Ehr. K.) 



Stauroneis aspera (Ehr. Kutz.) 



S ■ — (? Sp.) small, acutely rhomboidal, stauros narrow, 



reaching the margin, striae inconspicuous. Length 1.390." 

 Genus PLEUROSIGMA (Smith. Gyrosigma, Hassall.) 

 Pleurosigma iEstuarii ? (Breb. Sm.) 



P balticum (Ehr. Sm.) 



P ■ intermedium? (Sm. 



P strigilis ? (Sm.) 



P inflatum (Shadbolt.) 



FAMILY XIX.— ACTINISCEJE. 

 Genus DICTYOCHA (Ehr.) 

 Dictyocha Epiodon (Ehr.) 

 Genus MESOCENA, (Ehr.) 

 Mesocena octogona (Ehr.) 

 M binonaria (Ehr.) 



The foregoing list contains in all sixty-two species, belonging to 

 thirty Genera ; some of those I have described are probably new to 

 Science, but in the absence of authenticated specimens or even 

 drawings of, nearly all, the species foreign to Great Britain, I have 

 considered it prudent to leave them unnamed, and whenever I 

 have had any doubt of the identy of a species I have signified it 

 by adding a note of interrogation. 



It is probable that when I have had time to examime the larger 

 supply lately received, and for which I am indebted to the kind- 

 ness of Captain Castor, that the number of sp ecies will be at least 



* Note, — Of that species in Pritchard's Infusoria. 



