218 DESCRIPTION OF [Polygastrica. 



felt. It is found in a fossil state in the Isle of France 

 and Bilen. Length of single specimens l-570th to 

 1 -430th. 



280. 'BACiL.L.ARiA.pectanalis. The comb-like Bacillaria, or 

 the Dlatoma tenue of Agardh's Algae, has a striated slender 

 lorica, very often three to six times longer than it is broad ; 

 it is of a brownish -yellow colour. Nine striae in l-100th of 

 a line. Found both in fresh and sea waters. Length of 

 single rods 1 -3240th to l-430th. 



281. BACILLARIA elongata. The elongated Bacillaria 

 has a slender striated lorica, slightly attenuated in the 

 middle, as seen in group 169. Twelve transverse striae in 

 l-100th of a line. Length of single specimen l-l 150th to 

 1 -240th. 



282. BACILLARIA cuneata. The wedge-like Bacillaria 

 is striated, and of the form shewn in the engraving, 

 fig. 170. Found in fresh water. Length 1-1 150th to 

 l-1200th. 



283. BACILLARIA Cleopatrae. Cleopatra's Bacillaria has 

 an oblong lorica, destitute of striae. This species is of a 

 golden-yellow colour, and was found by Ehrenberg near 

 the ruins of the Baths of Cleopatra. Length l-570th to 

 1 -480th. 



284. BACILLARIA (?) tabellaris. The tablet Bacillaria has 

 a narrow smooth lorica, slightly enlarged at the middle ; 

 when adhering together they form square plates of variable 

 lengths ; ova yellowish, and divided. Found upon Con- 

 ferva glomerata. Length of single rod l-H50th to l-960th. 



285. BACiLLARiAjtfoccw/osa. Thefloccose Bacillaria has 

 a smooth lorica, almost square, and not enlarged at the 

 middle. Length 1-1 440th. 



