Ichtkyditia.'] INFUSORIAL ANIMALCULES. 607 



genera it is baud-like, long, elliptical, and upon the ventral surface. 

 A forked foot-like process is met with in Chaetonotus and Ichthydium, 

 and a simple one in the others. A simple conical alimentary canal, 

 with a long thin oesophagus, without teeth (?), is seen in Ichthydium 

 and Chaetonotus ; Glenophora has a short oesophageal portion, and 

 two single teeth, and Ptygura an elongated stomach and three 

 teeth. Pancreatic glands are seen only in Chaetonotus a,ud Ptygu?'a; 

 neither csecum nor gall-ducts are visible in any of the genera. The 

 male reproductive organs not observed ; the female consist, in two 

 genera, of a large ovarium, with a few large ova. The two red 

 frontal eyes, seen in Glenophora, are indications of the existence of 

 a nervous system, and the bristly hairiness of the back of Chaetonotus 

 is worthy of notice. 



This family comprises the following genera : 



Iwith a simple tmncated tail-like foot i p4.„_,_. 



"^ ' with a forked tail-like foot Ichthydium. 



L hair (bristle-like) present Chaetonotus. 



Eyes present (two frontal) Glenophora. 



This family is not admitted in Dujardin's system ; but the genera 

 Ichthydium and Chaetonotus are included among Infusoria (Poly- 

 gastrica) ; whilst Ptygura is placed in the family ' Melicei'tiens ;' 

 and Glenophora not recognised. Siebold likewise does not accept 

 the genus Glenophora. 



Genus Ptygura.— 2%e wrinkle-tailed Animalcules are destitute 

 of eyes and hair, but have a simple, truncated, cylindrical false foot. 

 Body campanulate, oblong. Rotatory organ simple, and nearly 

 circular. Numerous teeth-like bodies, adhering to the bulb of the 

 oesophagus, two pancreatic glands, a small narrow 03sophagus, an 

 elongated stomach, and a globular-like rectum, constitute the appa- 

 ratus of nutrition. An ovarium and a contractile vesicle have been 

 observed ; but neither longitudinal muscles nor visual organs, 

 although carefully sought for. 



This genus Ptygura is comprehended in the family Melicertiais 

 of Dujardin, along with Lacinidaria, Tubicolaria, and Melicerta, 

 and is made to include the species distributed by Ehrenberg in the 



