144 THE AMERICAN MONTHLY [May 



transversely truncate and including oral aperture; pos- 

 terior evenly roanded; heavily striate longitudinally; the 

 spaces intervening finely and closely striate transversely 

 oral cilia longer than body cilia, but not setose; contrac- 

 tile vesicle large and postero-terminal; nucleus roundish 

 and sub-central; oval aperture to one side and just above 

 the contractile vesicle; endoplasni granular; locomotion 

 even and by revolution on long axis. Size 1-500 inch. 

 Habitat — Fountain water with aquatic plants. 



This form would, if it possessed the setose oral cilia^ 

 certainly be classed as a Plagiapogon- Ehrenberg. The 

 very heavy longitudinal striation, which are almost band 

 like in this new form, and the line transverse striation of 

 the intervening spaces are also characteristic of the genus 

 Plagiapogon. In its habits it is the same scavenger that 

 the Coleps hirtus is. 



Family. — Lembidse. S. K. 



Genus. — Lembus. Colin. 



Species. — Lembus attenuata. (fig. 16.) 



Body elongate, subeylindrical; elastic but persistent in 

 shape: about six times as long as widest part; widest at 

 the center and tapering to both extremities; anterior 

 transversely truncate; posterior ending in a sharp point, 

 an undulating membrane and a furrow commencing just 

 behind the anterior border and extending backward to 

 the oral aperture, which is situated at the junction of 

 the first and second body fourths; body sparingly clothed 

 with cilia and these cilia as long as the widest central 

 part of the body; oral cilia same size as body cilia but 

 more numerous; undulating membrane capacious and 

 extending as far out as distal ends of oral cilia; contrac- 

 tile vesicle conspicuous and situated centrally near the 

 ventrum; endoplasm bluish and semi-opaque, locomotion 

 vermicular. 



Size 1-325 inch. Habitat-Stale pond water. 



