OF THE OPHEYDINA. 599 



Forming Monad-clusters, tlu-ough incomplete self-division of the lorica Ophrydium. 



/ Body furnished with an elastic pedicle attached 1 m- ^• 



! to lorica J ^'^ muu- • 



Lorica stalkless Vaginicola. 



Animalcules solitary, no J 

 self-division of the lorica "^ 



Body stalkless. 



Lorica stalked Cothurnia. 



Of the genera composing this family, Ophrydium is arranged by Dujardin 

 with the Urceolarina, and Vaginicola with the Yorticellina. This author 

 writes — 



*' The so-called lorica of Oplirydia (Duj., or Oplirydium) is an amorphous 

 gelatinous investment, unlike that of Vaginicola, which is a truly resistant 

 enveloping membrane. The individual beings in the gelatinous ball of 

 Oplirydia are elongated, cylindrical, or fusiform, and capable of varying their 

 figui^e." 



Further, Dujardin includes Tintinnus and CortJiurnia in the genus Va- 

 ginicola. 



Stein enumerates Tintinnus among the genera of Ehrenberg's Ophrydina, 

 but offers no account of it. He rejects the distinction, as does Dujardin, 

 between Vaginicola and Cothurnia, and would transfer the whole of this 

 family, so reduced, to Yorticellina, with which its members have the greatest 

 similarity in organization. Perty adopts the the title Ophrydma, but com- 

 prehends under it only the single genus Opjhrydimn. Lachmann rejects 

 Tintinnus from the list. 



The characters laid down by Ehrenberg, of this family, are very unsatis- 

 factory. Its members cannot be said to be loricated in the same way as 

 Colepina or Euplotina ; for in these the lorica consists of a thickened, closely- 

 adlierent integument, whilst in Ophrydina the structure so called is a loose 

 sheath, open at one extremity, which may in some be seen gradually excreted 

 from and built up around the animalcule, which last, moreover, has a distinct 

 integument of its own. In the Ophrydina, therefore, it is rightly called a 

 sheath, case, or tube. Ophrydium, indeed, is exceptional; for, though it 

 secretes a large quantity of miico -gelatinous substance, it never builds this 

 up around it into a sheath, but merely sends into it a long, tapering, fibrous 

 prolongation from its posterior extremity to secui^e a firm hold, whilst its 

 body projects freely from the mass (see Part I. p. 282). Moreover, it is 

 this genus only that is aggregated, all the rest being solitary. These pecu- 

 liarities may be held to justify Perty in erecting this genus into a family. 



The presence of numerous stomachs and of a distinct alimentary canal, it 

 need only be said, are details of organization requii^ed by the hypothesis of 

 Ehrenberg, and supposed in some instances to be demonstrated by feeding 

 with colouiing matters. 



As Ehrenberg rightly intimates, Ophrydina may be briefly defined as Yor- 

 ticellina living in a sheath, instead of being supported on a pedicle. From 

 this general definition Ophrydium is necessarily excluded as an exceptional 

 form ; and it becomes, therefore, a matter of regret that a family should be 

 named from a genus in no sort its true type. Perty has invented the name 

 " Yaginifera " for a family containing the two genera Vaginicola and Co- 

 tliurnia ; and it is certainly preferable to Ophrydina, whether Ophrydium be 

 comprehended in it or not. 



Genus OPHRYDIUM (XXX. 5, 6). — Lorica gelatinous ; animals clustered, 

 in consequence of perfect self-division of the body, but imperfect of the 

 lorica. This circumstance gives rise to very peculiar external appearances ; 



