Mr. H. J. Carter on the Organization of Infusoria. 357 



"moveable " contents are rotated, while the outer surface appears to 

 be attached to the diaphane, and follows its motions. In the Dia- 

 tomese, the sarcode appears to be separated from the diaphane by 

 the siliceous shield or frustule, as in a locomotive species of Palmogloea 

 met with by the author, where the cell-wall corresponds to the frus- 

 tule, and in Euglena^ where a layer of spiral fibre appears to be its 

 analogue. 



MoleculcB, or small grains. — With these the sarcode is completely 

 charged. They are colourless and vary in size, being sometimes 

 hardly visible, while at others they are uniformly large and unmis- 

 takeable. Of their use the author is ignorant, but for the sake of 

 distinguishing them from the other organs of the sarcode, he has 

 adopted the term above mentioned. 



Granules^ or large grains. — These are bodies of circular, elliptical, 

 elongated or irregular figures. They are always few in number when 

 compared with the moleculcBy and are characterized by their larger 

 size, thick, dark edges, and colourless appearance, except in some 

 Rhizopoda, where they bear a yellow substance like endochrome. 

 They undergo rotation with the other contents of the sarcode, and 

 never appear to be discharged. When ovules are present, as in 

 Amoeba, they are easily distinguished by the latter being discoid, 

 circular, transparent at the margin, and generally nucleated. Of the 

 use of the granules the author is also ignorant, but being sufficiently 

 constant and remarkable to deserve particular notice, he has pro- 

 posed this name for them. 



Digestive Globules. — These are spherical spaces of the sarcode 

 which are filled with food and water, or, sometimes, with water 

 apparently alone. They are formed in a fold of the pellicula in 

 Amoeba, &c., and at the inner end of the buccal tube in Paramecium 

 aurelia and Vorticella, &c., after which they pass into the midst of 

 the sarcode, and are there rotated until their contents are digested 

 and absorbed, or a part of one or both are discharged as unnecessary 

 for nutrition. Where there is a buccal tube, the water and particles 

 of food are forced down together through it, directly into the sarcode 

 at its extremity, and here the digestive globules are formed, which 

 afterwards pass off into the sarcode one after another gradually, like 

 soap-bubbles from a pipe. Their contents then undergo digestion, 

 and if not wholly absorbed, the rest passes out at a distinct anal 

 orifice, which is situated on the surface in Paramecium aurelia, &c., 

 and half-way up the buccal cavity in Vorticella. In the Amcebce, 

 &c., as before stated, there are no apertures of external communication 

 of this kind, and no cilia ; therefore the introduction of food is wholly 

 effected by the diaphane. For these temporary stomachal dilatations 

 of the sarcode the author has adopted the term above mentioned. 



Spherical Cells, or Biliai'y Organisms. — These are spherical cells 

 which abound in the sarcode of some of Ehrenberg's Trachelina, but 

 more particularly in an infusorium of the same family which the 

 author has called Otostoma, and in which they have been chiefly 

 studied. They appear to undergo rapid multiplication and decay, 

 and therefore are present in all stages of development. The most 



