Bacillaria.] THE INFUSORIA. 235 



343. FRUSTULIA maritima. The sea Frustulia. Lorica 

 smooth (?) ends rounded, multiplying in groups, in sepa- 

 rate, though contiguous, gelatinous cellules. Found, in salt- 

 water, at Swansea. Length 1-1 200th to 1-1150. 



344. FRUSTULIA salina. The salt Frustulia. Lorica 

 striated, very straight and acute, developed in a contiguous 

 gelatinous mass. Found in saline solutions. Length of 

 wands l-2300th to 1 -860th. 



Genus LXXIV. SYNCYCLIA. The ring little ship Ani- 

 malcules. Characters : a double envelope ; inner one, or 

 lorica, siliceous, Navicula- shaped ; external one indefinitely 

 formed, and gelatinous. The lorica is developed, by decus- 

 sating self- division, in clusters, within the gelatinous 

 mass, Ehrenberg states there are two openings near the 

 middle, on one side, but they are indistinct. 



345. SYNCYCLIA salpa. The tube little ship Animalcules. 

 Lorica semi-ovate, and smooth ; they are often jointed 

 together, so as to form six ring-like tubes ; the ova are 

 bright green. In the engraving, fig. 206 represents five 

 groups, imbedded in their gelatinous envelope, which resem- 

 bles slime upon sea-weed. The upper figure to the right 

 is a single creature ; the lower figure is an end view of a 

 cluster of six ; the other figures are side views. Length 

 1 -2300th to 1-5 70th. 



Genus LXXV. NAUNEMA. Characters : a double enve- 

 lope ; inner one, or lorica, siliceous, and Navicula- shaped ; 

 external one, or mantle, gelatinous, and tubular. From the 

 self-division of the lorica and body being perfect, and that 

 of the mantle imperfect, they are developed in separated 

 filiform tubes, often branched, presenting a conferva-like 

 appearance. The lorica is incombustible, but the mantle 



