Closterina.'] THE INFUSORIA. 149 



114. CLOSTERIUM turgidum. The turgid Closterium. 

 Lorica stout, slightly curved, and approaching to cylin- 

 drical, a little attenuated at both ends, apices of a reddish 

 colour, and rounded ; obscurely marked with smooth striae. 

 This is one of the largest species of the genus, and was 

 formerly mistaken by Ehrenberg for the C. ruficeps, on 

 account of the red apex. The delicate streaks or markings 

 of the lorica, which m ay be considered as the main charac- 

 teristics of the species, had been overlooked. Fig. 66 

 represents a living Closterium, having three animated (?) 

 clusters of granules within it ; the lorica is supposed to be 

 opened, the mass of green matter being ova. Length 

 l-140th to l-60th. 



115. CLOSTERIUM lineatum. The lined Closterium. 

 Lorica of considerable length, often thirty times as long as 

 broad, slender, and slightly curved ; cylindrical and filiform 

 at the middle, but greatly attenuated and truncated at both 

 extremities. It is distinctly marked with smooth lines. 

 Found amongst conferva. Length 1 -200th to 1-3 6th. 



116. CLOSTERIUM striolatum. The striated Closterium. 

 Lorica spindle-shaped and arcuated, ten to twelve times 

 as long as broad ; slightly attenuated and truncated at both 

 ends. It is obscurely marked with smooth striae. Found 

 amongst oscillatoria. Length 1-1 20th. 



117. CLOSTERIUM setaceum. The bristle-shaped [Closte- 

 rium. Lorica spindle-shaped, straight, or very slightly 

 arcuated, and almost insensibly striated, having setaceous 

 horns, each horn being longer than the body. The empty 

 shell-like projections, which Ehrenberg has designated 

 setaceous horns, are rounded at the extremities, but so 

 attenuated as not to allow of any openings being seen. 



