ORGANS OF ATTACHMENT 



39 



(Fig. 18, i). Similarly, amongst the Ciliata filaments of attachment, either 

 simple or branched, may be developed. In some cases, as, for example, 

 Vorticella, the filament contains a contractile thread, by means of which 

 it can be suddenly coiled up in a spiral manner and the ciliate withdrawn 

 when it is subject to adverse stimuli (Fig. 19). 



Amongst parasitic Protozoa, many gregarines are provided with 

 special organs of attachment. The young organism which develops from 

 the sporozoite is at first intracellular, but as growth occurs it leaves the 

 host cell, to which, however, it remains attached by a process known as 

 the epunerite (Fig. 20). This structure is developed in various ways, 

 and may be compared to the organ of attachment of tape-worms. It 



Fig. 19. — VoHicella nehulifera : A Group of 



Stalked Ciliates attached to an Object 



( X 200). (From Lang. 1901, after 

 d'Udekem.) 



1. Contractile vacuole; 2, daughter individual with 

 circlet of cilia; .3, dividing form; 4, conjugation. 



m 



Fig. 20. — A Cephaijne Gre- 

 GARINE {Corycella armata) 

 ( X ca. 300), showing 

 Epimerite, Protomerite, 



AND DeUTOMERITE. (AfTER 



Leger, 1892.) 



may be a simple swollen body embedded in the cytoplasm of the cell, 

 and connected with the parasite by a kind of neck, or there may be de- 

 veloped from it a series of filaments or roots which anchor the parasite 

 to the cell. In some cases a large sucker-like process is applied to the 

 surface of cells, and from it a series of filaments pass into the cells or 

 between adjacent cells. In other cases the epimerite is supplied with a 



