The microscope and its revelations . y assertions of the same classfirst appeared, which are now admitted as miquestionable truths; and theyought not to be set aside without disproof, any more than they should bereceived without farther confirmation. PROTOZOA :—ACTLNOPHEYS. 467 have no definite boundaries, and may be easily made artificiallyeither to coalesce into larger ones, or to subdivide into contractile vesicle {o), pulsating rhythmically with greatregularity, is always to be distinguished either in the midst ofthe jelly-like substance, or (more commonly) near its surface;and t
The microscope and its revelations . y assertions of the same classfirst appeared, which are now admitted as miquestionable truths; and theyought not to be set aside without disproof, any more than they should bereceived without farther confirmation. PROTOZOA :—ACTLNOPHEYS. 467 have no definite boundaries, and may be easily made artificiallyeither to coalesce into larger ones, or to subdivide into contractile vesicle {o), pulsating rhythmically with greatregularity, is always to be distinguished either in the midst ofthe jelly-like substance, or (more commonly) near its surface;and the appearance which it presents in this latter position,seems to leave no doubt of its being included within a distinctthough very tliin membrane. The sarcode extends itself intocontractile tentacular filaments, which are CdR^di pseudoj)Oclia;and these, in the Actinophri/s sol, are commonly seen to radiatefrom the centre, ia such a manner as to have suggested thedesignation of the species. Their degree of extension, how- FiG. // \l\\- Actinophrys sol, in different states :—a, in its ordinary sun-likeform, with a prominent contractile vesicle, o; b, in the act of divisionor of conjugation, with two contractile vesicles, o, o; c, in the act offeeding; d, in the act of discharging faecal (?) matters, a and h. ever, is extremely variable, and sometimes they entirelydisappear: the creature cannot tlien be distinguished withcertainty from an Amoeba. For although the form of thelatter is generally flattened, yet it sometimes becomes nearlyspherical; so that neither type can be recognized, lantil thejelly-like spherule flattens itself out as an Amoeba, or puts-forth radiating pseudopodia as an Actinophrys.—Far lessHH 2 468 MICEOSCOPIC rOEMS OP ANI3IAL LIFE. activity is exhibited by Actinophrys, than by Amoeba; andthe slight change of place which it undergoes from tune totime, does not seem attributable either to any change of formof the body, or to any bending of the tentac
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