OF THE (ECISTINA. 



663 



be considered teeth ; glands are indicated by knot-like turbid bodies. The 

 eyes are sharply circumscribed, and situated at the frontal region. Dujardin 

 and Leydig believe this genus to h% based on young animals, and as such 

 unsatisfactory. 



Glenophora Trochus. — Ovato-coni- 

 cal, truncated and turgid anteriorly, at- 

 tenuated posteriorly, ^\dth a false foot ; 

 the eyes are blackish. It swdms quickly, 

 like a Trichoda or free Vorticella. The 



genera Monolahis and Microcodon have 

 similar forms, (xxv. 359, 360 represent 

 two animalcules, the latter havmg the 

 stomach filled with a gi-een substance.) 

 1-570". 



FAMILY II.— (ECISTINA. 



Rotatoria with a single rotary organ, entire at the margin, and an ex- 

 ternal gelatinous envelope. This family contains only two genera, which 

 possess a more developed internal organization than any hitherto described. 

 They are further provided, according to Ehrenberg, with locomotive organs, 

 internal muscular bands, a tail- like foot without terminal pincers ; nutritive 

 organs, among which is a crushing apparatus consisting of teeth in rows ; 

 two pancreatic glands, and red visual or eye- spots. In Conochilus alone he 

 thinks he observed ganglia with nervous fibrillae, male organs, vessels, and 

 two filiform tremulous organs or gills. 



This description is of course modified by the views Ehrenberg entertains 

 respecting the various organs contained in the bodies of these animals. We 

 have no evidence that the glands are pancreatic ; the " male organs " are 

 the w^ater-vascular canals of other writers, of which the tremulous organs or 

 giUs are external appendages; the "vessels" are muscular bands; and the 

 nervous fibrillae and ganglia have a more than doubtful existence. 



{Special for each animalcule CEcistes. 

 Compound, or common to many animalcules Conocliilua. 



Both the (Ecistes and Conochilus are included by Leydig in his first division 

 of Rotatorial animals. 



Genus (ECISTES (XXV. 361-364).— Characterized by each animalcule 

 ha\dng a separate lorica. The two eyes, situated anteriorly, become eflPaced 

 as age advances. Ciliary wreath simple and frontal ; the long tail-like foot 

 has internal longitudinal muscles. Alimentary canal simple, tubular, con- 

 tracted ; stomach elongated ; teeth attached in rows to two jaws situated in 

 the pharyngeal bulb, and two glands, compose the apparatus of nutrition. 

 The visual organs are red when the animalcule is yoimg, and colourless in 

 old age. The ovarium has only a single ovum. The envelope is a viscid, 

 gelatinous, cylindiical sheath (urceolus), into which the animalcule can 

 entirely withdraw itself, or which it may quit when a new one is desirable. 

 The attachment to the bottom of the lorica is by the under surface of the end 

 of the foot-like tail. 



(Ecistes crystallimis. — Lorica hj^a- 

 line, viscid, floccose ; body crystalline. 

 The structure it is difficult to see. Each 

 jaw has three distinct teeth. The de- 

 velopment of the young from the egg 

 is interesting to observe : Ehrenberg 

 saw within the shell two dark points 

 (eyes) near the already developed jaws -, 



and on giving the egg a gentle pressm'e 

 it burst, and the free young animal 

 came forth (xxv. 361, a full-grown ani- 

 malcule in the act of unfolding itself; 

 362, another with its rotaiy organ ex- 

 panded). Their sheaths are incrusted, 

 and within may be seen a number of 

 eggs (363, 364 represent them attached 



