GENUS ACINETA. 835 



to that more conspicuously developed in Podophrya elongata, as also that the 

 tentacles, when extended, are capable of flexure in various directions. l\Ir. Phillips 

 has attested in his communication to having on one occasion observed a brood of 

 flagellate organisms escape from an otherwise uninhabited lorica. At first 

 sight these were supposed to have had some connection with the developmental 

 phenomena of the species, but is interpreted by the author as representing a case 

 only of the intrusion and reproduction of a Flagelliferous form within the vacated 

 domicile of the Acinetan. 



Acineta Jolyi, Maupas. Pl. XLVIII. Figs. 34 and 35. 



Lorica exceedingly compressed, irregularly quadrate, about one and a 

 quarter times as long as broad, the lowermost angle, which is united with 

 the pedicle, being the most attenuate ; the anterior and two lateral angles 

 abruptly truncate, leaving ovate apertures for the extrusion of the tentacles ; 

 pedicle slender, rectilinear, somewhat longer than the lorica ; contained 

 animalcule occupying the greater portion of the cavity of the lorica ; 

 tentacles forming three — one anterior median and two lateral— fascicles 

 corresponding in position with the apertures in the lorica, their bases 

 apparently produced into the central region of the body ; contractile vesicle 

 subcentral, anteriorly located ; cndoplast discoidal, occupying a similar 

 position towards the posterior region of the body. Length of lorica 

 l-i2o". Hab. — Salt water, Algiers. 



This species, on account of its greatly compressed contour and corresponding 

 tenuity as seen in profile, is exceedingly transparent. With respect to its possession of 

 three tentacular fascicles, it differs distinctly from all species of the genus previously 

 described, while Podophrya pyrum is the only type among the illoricate forms in 

 which an analogous plan of distribution obtains. According to M. Maupas, its dis- 

 coverer, the contractile vesicle is remarkable for the length of time that intervenes 

 between its contractions, as much or more than an hour not unfrequenlly representing 

 this interval. As in many allied species, this vesicle is formed by the flowing 

 too-ether of numerous smaller lacunae. The nucleus or endoplast in examples 

 treated with a one per cent, solution of osmic acid was found to enclose numerous 

 transparent vacuoles having a central refringent corpuscle, while in many instances 

 there was attached to the lateral periphery of this structure a minute spherical body, 

 which probably represents an endoplastule. 



B.— Tentacles irregularly distributed. 



Acineta patula, C. & L. Pl. XLVL Figs. 45-47- 

 Lorica cup-shaped or infundibulate, tapering posteriorly, widest at its 

 anterior margin, seated on a long rectilinear stem with a narrow constriction 

 at the point of junction between the two ; body equal in height to the 

 lorica, ovate or spherical, its lower extremity only resting within the lorica 

 and not adherent to it ; tentacles distinctly capitate, very long and slender, 

 protruded from every portion of the periphery. Height of lorica without 

 the stalk 1-85" to 1-50". Hab.— Salt water, on Algae. 



The aspect of this elegant animalcule, seated in its long-stalked cup-like lorica, 

 and with the tentacula withdrawn, is fancifully suggestive of the children's toy dis- 

 tinguished by the familiar title of " cup and ball." Both conjugation and the pro- 

 duction by the individual animalcules of a singlfe embryo, apparently ciliated 



2 B 2 



