Euj)lota.'] INFUSORIAL ANIMALCULES. 599 



The animalcules of the genus ' Plaesconia ' seem for the most part 

 identical with the Euplutes of Ehrcnberg, but as the identification 

 is in some cases uncertain, and as several new species are described 

 by Dujardin, we shall subjoin the Ploesconia, as constituting an 

 appended genus along with Diophrys and Cocciidina. 



Genus Discocephalus. — T7te disc-headed Animalcides have 

 neither styles nor teeth, but possess unciui, and have the head 

 distinguished from the body (capitate). The organization is un- 

 known, only the non-vibratile uncinated locomotive organs having 

 been specially observed. 



D. rotatorius. — Body transparent, flat; head smaller than the 

 body; both rounded. Fig. 345 is an under, and fig. 346 a side 

 view. Found in the Red Sea. Size l-380th. 



Genus Himaj^tophokus. — The whip-footed Animalcides are dis- 

 tinguished by the absence of styles and teeth, by having numerous 

 uncini, and not having the head distinct from the body. The long 

 bent hooks, generally in pairs, appear like a broad band upon the 

 under side, serving as organs of locomotion ; near them is a row of 

 cilia extending from the mouth to the middle. The mouth, dis- 

 charging orifice, and numerous digestive cells, are distinct. At the 

 posterior margin is a large contractile vesicle ; between the row of 

 cilia and margin on the right is a series of glandular spots. Self- 

 division has not been observed. 



H. charon (M.) — Body transparent, flat, elliptical, anterior 

 slightly truncated obliquely, cilia short, uncini long and slender. 

 The mouth commences anteriorly at the lower angle of the tri- 

 angular bright spot, but the true oesophageal opening appears to be 

 at the end of the row of cilia within the curved lorica ; the posterior 

 alimentary opening is nearly at the base of the last cluster of four 

 to six comb-like uncini, which supply the place of styles. Fig. 347 

 is a side, and fig. 348 an under view. Found in water vessels that 

 have stood some time. Size 1-1 80th. 



Genus Chlamidodon. — The toothed Animalcules possess ciha 

 and teeth at the mouth, but no styles or uncini ; an oval trans- 

 parent lorica or shield covers the back, and projects around it ; a 

 margin of cilia surrounds the body, these are longer near the brow ; 

 short climbing setse probably exist posteriorly, between the cilia. 



