SfiS DE8CHIPTI0N OF {Tolygostrica. 



having thi'ee strong spines. Found in the body of Spirostomum 

 virens. Size 1 -280th. 



C. incurrus. — Body oblong, nearly cylindrical, and slightly curved ; 

 lorica tal)ulated and terminating in five points. Found amongst 

 Conferva. Size 1 -430th. 



Family TRACHELmA 



This extensive family includes those animalcules which have an 

 alimentary canal with two distinct orifices, the receiving one lateral, 

 the discharging one terminal ; but have no lorica. The bodies of all 

 the genera, except Pkialina, are covered with vibrating cilia, gene- 

 rally disposed in longitudinal rows, and those near the mouth longest. 

 The cilia serve as organs of locomotion. Trachelius has no neck, but 

 the frontal portion of the bodj^ is prolonged in the form of a long 

 proboscis-like lip ; in Loxodes and Chilodon it is like a hatchet- shaped 

 broad lip. In Glaucoma there is a tremulous flap to the mouth ; and 

 in Chilodon and Nassula the teeth sometimes project before the mouth. 

 The genera Bursaria and Nassula have a thick frontal protuberance, 

 caused by the alimentary canal being curved anteriorly ; numerous 

 stomach-ceUs are observable, and their reception and discharge of 

 coloured matter can be seen in all the genera. The teeth in Chilo- 

 don and Nassula, and the violet-coloured bile (gall) of the latter 

 genus, are worthy of notice. In S^nrostomum the mouth is of a 

 spiral shape. Reproductive organs are of a double kind in all the 

 genera. Complete transverse and longitudinal self-division is fre- 

 quent, but neither the formation of gemmae nor clusters are 

 observed. 



The genera are disposed as follows : — 



!/ ~ /■ with a i lip long, proboscis-like . . Trachelius. 

 ^ brow-like I 

 brow 'x J upper lip. ( lip broad, hatchet-shaped . . Loxodes. 

 continuous - ■£ I 

 with the Q [^brow-liko prominent back Bursaria. 



mouth body. I £ 

 flap. \ Mouth spiral .-.Spirostomum 



^Brow discontinued in a peg-like manner , Phialina. 



' Mouth having a tremulous flap Glaucoma. 



,g p I A brow-like prominent upper lip Chilodon. 



H »^ ( A brow-like prominent back Nassula. 



