146 HOFMEISTELl, ON 



occasionally be seen in the actual process of constriction 

 (PL XVIII, fig. 4). 



The perfect chlorophyll-bodies are small ellipsoids, some- 

 what flattened in the direction of the shorter axis, and 

 having the substance of their periphery somewhat denser 

 and more strongly coloured than that of their interior, so 

 that they present a vesicular appearance. They usually 

 contain one or more very small starch-granules. 



In young leaves of Phascum cuspidatum, also, the less deve- 

 loped cells exhibit only one or two large chlorophyll-bodies ; 

 in more fully developed cells they become continually more 

 numerous and smaller. The perfect bodies have a vesicular 

 appearance, and usually contain several starch- granules ; 

 when the cell which surrounds them is ruptured, so that water 

 is brought in contact with them, their entire mass swells up 

 largely, running together ultimately into a shapeless jelly. 



The previously described process of the formation of the 

 large chlorophyll-bodies of Anthoceros is similar to that 

 here mentioned. Prom these facts I drew the conclusion* 

 that in young cells the chlorophyll is colourless, inasmuch 

 as the colouring matter is dispersed throughout the muci- 

 laginous cell-contents in the form of immeasurably small 

 particles. As the development of the cell proceeds, the 

 coloured portions unite to form globular drops, which are 

 capable of multiplying themselves by division. This opi- 

 nion was opposed to that of Nageli (' Zeitschr. f. wissensch. 

 Bot.,' H. 3 & 4, Zurich, 1846, 111), who assumes that the 

 chlorophyll-bodies originate in the form of small, coloured 

 granules, which gradually increase in size : it was, however, 

 in accordance with Nageli's view to the extent of assuming 

 a vesicular structure in the chlorophyll-bodies, and it con- 

 firmed the fact, first pointed out by Nageli, of the division 

 of the latter bodies. The idea of a vesicular structure in 

 the chlorophyll-bodies was opposed by H. v. Mohl, who 

 relied upon certain appearances exhibited by those bodies 

 when distended with water (' Bot. Zeit.,' 1855, 107, 109); 

 but v. Mohl also, having eventually modified an earlier opi- 

 nion, came to the conclusion that, however chlorophyll may 



* ' Vergleichende UntersuchuDgeu/ Lpz., 1851, p. 10. 



