838 ORDER TENTACULIFERA-SUCTORIA. 



circle, the two lateral and a median posterior angle being left intact, a 

 narrow fissure-like cleft slightly widened at its two extremities, extending 

 along the front border between the two lateral angles ; pedicle slender, 

 rectilinear, very short, not exceeding one-half of the diameter of the lorica ; 

 body of animalcule rarely occupying more than the anterior moiety of the 

 cavity of the lorica, often limited to a narrow lunate or fusiform granular band 

 adherent to its upper wall ; tentacles distinctly capitate, very short, varying 

 from two or three to as many as fifteen in number, distributed irregularly 

 along the frontal border, and protruding from the fissure-like cleft of the 

 lorica ; contractile vesicle single ; endoplast spheroidal or ovate. Diameter 

 of lorica 1-350". HAB. Saltwater: Algiers. 



Acineta stellata, S. K. PL. XLVI. FIGS. 32-35. 



Lorica subpyriform, its cavity continued inferiorly into a short, gradually 

 tapering, hollow, stalk-like attachment, its lateral walls at the points of 

 exit of the tentacula produced outwards as fine radiating tubuli ; contained 

 body subglobose or stellate, the tentacles capitate, their length when 

 extended exceeding the diameter of the body, varying in number from six 

 or seven to as many as twelve, radiating from all parts of the periphery, 

 and perforating the substance of the lorica ; contractile vesicle, single ; 

 endoplast spheroidal, subcentral. Height of entire lorica 1-1500" ; diameter 

 of body 1-3000". HAB. Pond water, on Conferva. 



This species was obtained by the author, in August 1871, attached in con- 

 siderable quantities to Confervas taken from a pond at Stoke Newington, London. 

 Its excessively minute size readily distinguishes it from all the forms hitherto 

 described, while, at the same time, the general contour, with its characteristic 

 attachment, consisting rather of a tapering prolongation of the lorica than of a 

 distinct pedicle, corresponds to some extent with that of the short-stalked variety of 

 Acineta mystacina, delineated at Fig. 41 of the same Plate. The characters afforded 

 by the disposition of the tentacles and their relationship with the investing lorica 

 are entirely at variance with that form or any previously recorded type. As intimated 

 in the foregoing diagnosis, these tentacula radiate in all directions, and appear to as 

 it were perforate the wall of the lorica rather than to issue from any definite 

 apertures or fissures in its substance. Such perforation of the walls of the lorica must 

 evidently take place during its newly formed, mucilaginous condition, it being only 

 at this time sufficiently soft to permit the tentacles to push before and carry out with 

 them slender tubular prolongations of its substance. That these tubular prolonga- 

 tions of the walls of the lorica have a substantial existence is best demonstrated by 

 an examination of the animalcule in its encysted condition. In this state, notwith- 

 standing that the body is shrunk up into a compact globular form within the central 

 cavity, tentacule-like processes are still to be seen radiating from the walls of the 

 lorica ; these, however, have no capitate extremities, and are found, on closer 

 investigation, to be entirely disconnected from the central encysted body, and to 

 be merely slender, hollow extensions of the lorica-wall, as shown at PI. XLVI. 

 Figs. 33 and 34. It was not unfrequently observed that the body of the animal- 

 cule inside these characteristic encystments, as delineated in the first of the two 

 figures quoted, had divided into two by transverse cleavage. Sometimes the pedicle- 

 like portion is so short and inconspicuous as to present the character only of the 

 ordinary tubular prolongations of the lorica associated with an extruded tentaculum, 

 and with which this structure, as demonstrated in the case of Podophrya mollis, is 

 without doubt originally homologous. Not unfrequently, again, the lorica was 



