GENUS HEMIOPHRYA. 825 



tentacle, in place of forming a crest-like ridge upon its external surface, as obtains 

 in H. gcmmipara. The embryos produced by terminal gemmation are, as in 

 Hertwig's species, hypotrichously ciliated, and manifest closely identical develop- 

 mental phenomena. It is recorded that the bodies of the adult animalcules easily 

 become detached from their supporting pedicles ; and on one occasion a ciliated 

 embryo was observed to crawl up and down, and finally aftix itself to the summit of 

 a deserted pedicle, and there develop to the adult form. This circumstance is 

 accepted by M. Fraipont as explanatory of the frequent occurrence of fully 

 developed pedicles having only very minute attached zooids. A similar result is, 

 nevertheless, not unfrequently brought about in allied species through the ordinary 

 process of transverse fission. 



Hemiophrya truncata, Fraipont sp. Pl. XLVIII. Fig. 46. 



Body elliptical or subquadrangular; pedicle massive and irregular, three 

 or four times the length of the body ; usually for some little distance 

 equalling the breadth of the body in thickness, and thence tapering 

 gradually to its point of attachment, its distal end articulate or transversely 

 plicate; suctorial tentacles developed from the centre of the distal region of 

 the body, the prehensile tentacles numbering in adult zooids as many as 

 fifty or sixty, more slender and prolonged than those of the suctorial series, 

 and around which they are chiefly disposed in a fringe-like manner; 

 parenchyma densely granular ; endoplast and contractile vesicle not 

 observed. Length of body 1-500". 



Hab. — Salt M^ater, on the Zoophyte Sertiilaria cupressina. 



This form is described by M. Fraipont as a species of Podophrya from specimens 

 collected and preserved at Ostend, by Professor Ed. Van Beneden. In the massive 

 character of the pedicle it differs in a marked manner from the two preceding species, 

 but at the same time somewhat resembles in this respect the Podophrya Stemii of 

 Claparede and Lachmann. In an encysted example observed the body-substance 

 had become subdivided into a mass of granular spore-like spherules. 



Hemiophrya microsoma, Maupas. 



Body subspherical or ovate, attached to a very long, cylindrical, 

 irregularly sinuous pedicle, the breadth of which is greatest at the distal 

 end, there equalling one-quarter or one-half the diameter of the body, and 

 gradually tapering towards its point of attachment, its length varying 

 from four or five to as much as eighteen times that of the body ; suctorial 

 tentacle single, subcentral, originating from the centre of the body ; pre- 

 hensile tentacles short, not exceeding eight or ten in number, developed 

 superficially, and irregularly scattered, their distal ends slightly inflated ; 

 contractile vesicle single or double ; endoplast elongate, irregularly nodu- 

 late. Length 1-900". Hab. — Saltwater: Algiers. 



The short dimensions of the body with relation to its supporting pedicle, 

 combined with the very small proportionate number of the suctorial tentacles, sepa- 

 rates this type very distinctly from its congeners. From the fact recorded by Maupas 

 that the tentacles belonging to the prehensile series are slightly dilated instead of 

 subulate at their free extremities, this species would seem to represent an annectant 

 form between the typical members of the two genera Hemiophrya and Podophrya. 



