5IO ORDER HOLOTRICHA. 



The animalcules of this genus, while somewhat resembling those of Holophrya, 

 are to be distinguished from the latter by their pointed and obliquely truncate 

 anterior extremity, and by the fringe of larger cilia that encircles the oral region. 

 The diagnoses and figures of the several species, as given by Ehrenberg, represent 

 them as having no cilia on the general surface of the integument, these structures, 

 while present, being so fine that they are liable to be overlooked unless glasses of 

 the highest defining power are employed in their examination. From Tric/ioda, 

 with which the animalcules of this generic group also closely correspond in form 

 and habits, they are to be distinguished by the absence of a vibratile membrane in 

 association with the oral fossa. The genus Enchclys of Dujardin does not cor- 

 respond with that of Ehrenberg, but includes forms rightly referable to the genus 

 Cydidmni. 



Enchelys farcimen, Ehr. Pl. XXVII. Fig. 15. 



Body transparent, pyriform, slightly curved, attenuate and obliquely 

 truncate anteriorly, inflated posteriorly, about one and a half times as long 

 as broad ; contractile vesicle single, spherical, posteriorly located; endoplast 

 oval, subcentral. Length of body i-iooo" to 1-430". 



Hab. — Stagnant water and infusions. 



The author has encountered a species agreeing in every respect with this form 

 but of smaller dimensions, in hay-infusions, the largest examples not exceeding the 

 thousandth part of an inch in length. The characteristic movements of these 

 animalcules consisted, when feeding, of routing about, snout downwards, among 

 the vegetable debris, as shown in the accompanying figure, and at other times 

 of swimming slowly through the water rotating on their longitudinal axis. In 

 common with the members of the genus Holophrya, this and the other species of 

 Enchclys become considerably distorted through the inception of food-substances, 

 that may even exceed themselves in bulk, and also assume at will an entirely 

 spherical outline. In this latter condition the oral aperture becomes completely 

 obliterated, the position of the contractile vesicle only under these circumstances 

 assisting in the distinction of the anterior from the posterior region of the body. 



Enchelys pupa, Ehr. 



Body inflated, attenuated anteriorly, frequently filled with green granules. 

 Length 1-140". Hab.— Stagnant bog water. 



Enchelys arcuata, C. & L. Pl. XXVII. Fig. 14. 



Body pyriform, attenuate anteriorly, perfectly transparent, cilia of general 

 surface very short and fine ; contractile vesicles numerous, four or five in 

 number, arranged in an arcuate manner along the ventral margin of the 

 body; endoplast elongate-oval, subcentral. Length 1-300". 



Hab. — Bog water. 



Doubtful Species, 



The so-called Hematozoon from the blood of Ceylon red deer, described and 

 figured by Dr. Boyd Moss in the ' Monthly Microscopical Journal ' for October 

 187 1, is apparently referable to the genus Enchelys. The animalcules there 

 delineated exhibit roughly the characteristic aspect of the members of this genus, 

 though the cilia, probably through imperfect illumination, Avere visible only upon 

 the more pointed anterior half of the body. Their dimensions would appear to 

 correspond most closely with the smaller size of those of E. farchncn. While the 

 evidence given by Ur. Moss strongly favours the supposition that these ciliate 



