Mr. H. J. Carter on the Organization of Infusoria. 121 



is not porDvittcd, and the cell is here closed after the manner of 

 vegetable cells generally. What further strengthens the view that 

 there is in some Diatomeje [e.g. Navicula and Nitzschia) a layer 

 corresponding to diaphane on the surface, is, that there is some 

 prehensile and transporting organ here, which undoubtedly has 

 the power of seizing particles that come in contact with it, and 

 of conveying them partially or wholly backwards and forwards 

 IVom one extremity of the frustule to the other, or of retaining 

 them on any part of it stationarily. Mii< ulaI -jHm I a )uiv/ ,' ..^>) 

 Moleculce. — We will apply this term to 'the minute, colourless 

 granules with which the sarcode is charged (fig. 3 b). They 

 differ in size, and are the first bodies that appear in it; but 

 whether they be of different kinds, have any particular office, or 

 undergo any further development, 1 am at present ignorant. 

 Amoeba J Astasia (fig. 45), and Euglena (fig. 46), in the earlier 

 [)art of their existence, respectively seem to contain nothing else 

 but this molecular sarcode, the nucleus, and contracting vesicle ; 

 afterwards the " granules ^^ appear, and last of all the ovules, 

 both of which are developed in the sarcode amongst the moleculae. 

 By the time the ovules have become fully formed, the sarcode and 

 its moleculai have died off, or disappeared (figs. 26, 46, 56). 



Granules. — This name is intended for certain large granules, 

 which make their appearance among the moleculse, and are cir- 

 culated round the abdominal cavity in the manner of the diges- 

 tive globules and particles of food (figs. 4 «, 5 c, 65 a). They 

 are of different sizes, but chiefly characterized by being much 

 larger than the molecula?, few in number, of a circular, elliptical, 

 elongated, sub-round, or irregular shape, with thick dark edges, 

 apparently produced by obstruction to the passage of light, — 

 colourless, or of a yellowish -green tint. When large, and with 

 no other granular matters present but the moleculse, they form 

 a striking feature in the interior of Amoeba, Vorticella, Oxytricha, 

 Paramecium awelia, &c. ; but at times they are so insignificant in 

 size as to be undistinguishable from the moleculse, even if present 

 at all. That they are not ovules may be satisfactorily seen when 

 both are together; the dark, thick, and frequently irregular 

 edges and colourless state of the former contrasting strongly 

 with the thin, circular margin and faint yellow tint of the latter 

 (fig. 5 c). They appear to increase in size and number with 

 the age of the infusorium, and, when fully developed, to remain 

 unaltered in size, though apparently somewhat shrivelled in 

 form, until their dissolution. On one occasion, while watching 

 the metamorphosis of an Oxytricha (similar to, but not the 

 same as that described by M. Jules Haime*, and of which I 



* Ann. des S^.,N9*f t. W& |i»*jlU9!^Zooi» 1853.. 



