of Chloroplasts and Leucoplasts . 113 
J 2 . Guilliermond, A. ( 1914 ) : Bemerkungen Qber die Mitochondrien der vegetativen Zellen und 
ihre Verwandlung in Plastiden. Eine Antwort auf einige Einwiirfe. Ber. der Deutsch. bot. 
Ges., vol. xxxii, 1914, pp. 282-301. 
13 . -( 1915 ) : Queiques observations cytologiques sur le mode de formation des 
pigments anthocyaniques dans les fleurs. Comptes Rendus, vol. clxi, 1915, pp. 494-7* 
14 . -( 1915 ) : Sur l’origine des pigments anthocyaniques. Ibid., pp. 567-70. 
Janssens, F. A. ( 1913 ): Le chondriosome dans les champignons. La Cellule, vol. xxviii, 
1913, pp. 447. 
-et Helsmortel, J. ( 1913 ): Le chondriosome dans les Saccharomycetes. 
Ibid., pp. 451-2. 
-et Van de Putte, E. ( 1913 ) : Le chondriosome dans les asques de Pustularia 
vesiculosa. Ibid., pp. 447-50. 
1 . Lewitsky, G. ( 1910 ): Ueber die Chondriosomen in pflanzlichen Zellen. Ber. d. Deutsch. bot. 
Ges., vol. xxviii, 1910, pp. 538-46. 
2 . -( 1911 ): Vergleichende Untersuchungen iiber die Chondriosomen in lebenden 
und fixierten Pflanzenzellen. Ibid., vol. xxix, 1911, pp. 685-96. 
3 . -( 1911 ) : Die Chloroplastenanlagen in lebenden und fixierten Zellen von Elodea 
canadensis , Rich. Ibid., pp. 697-703. 
1 . LOwschin, A. M. ( 1914 ): Vergleichende experimental-cytologische Untersuchungen iiber 
Mitochondrien in Blattern der hoheren Pflanzen. Ibid., vol. xxxii, 1914, pp. 266-70. 
2 . -( 1914 ): Zur Frage fiber die Bildung des Anthocyans in Blattern der Rose. 
Ibid., pp. 386-92. 
McAllister, F. ( 1914 ): The Pyrenoid of Anthoceros. Am. Jour. Bot., vol. i, 1914, 
PP- 79 - 95 * 
Mirande, Marcel ( 1916 ): Observations sur le vivant de la formation cytologique de l’antho- 
cyanine. Comptes Rendus, vol. clxiii, 1916, pp. 371-86. 
Rudolph, K. ( 1912 ): Chondriosomen und Chromatophoren. Ber. d. Deutsch. bot. Ges., 
vol. xxx, 1912, pp. 605-27. 
Sapehin, A. A. ( 1913 ): Ein Beweis der Individualist der Plastiden. Ibid., vol. xxxi, 1913, 
pp. 321-4. 
Scherer, A. ( 1913 ): Die Chromatophoren und Chondriosomen von Anthoceros. Ibid., 
PP* 493 - 5 °°* 
EXPLANATION OF PLATE I. 
Illustrating Professor Mottier’s paper on Chondriosomes and the Primordia of Chloroplasts 
and Leucoplasts. 
All figures were drawn from sections with the aid of the camera lucida. 
Fig. 1. A cell from the root-cap of Pisum sativum , Marrow P'at variety. In the upper or distal 
half of the cell are several starch grains (St.), in which the plastid appears as a dark, narrow crescent 
at one side. The dark granules and rods are chondriosomes. x 2,100. 
Fig. 2. A cell from the root-tip of Pisum , showing large rod-shaped primordia of leucoplasts 
and small, granular, and very delicate rod-shaped chondriosomes. The knob or head at one end 
of some of the primordia indicates the beginning of a starch inclusion, x 2,100. 
Fig. 3. An older cell from the central cylinder of the root. The transformation of primordia 
into leucoplasts is more evident. The starch inclusion in one end of the plastid is circular or oval, 
giving the leucoplast the form of a pear, club, or hand-mirror. The chondriosomes, as in the pre¬ 
ceding figure appear as granules or delicate, slender rods, x 2,100. 
Fig. 4. Leucoplasts from older cells of the central cylinder of the root of Pisum. a , chondrio¬ 
somes; c , d, and e , different forms of leucoplasts. At c the oval starch inclusion lies near the centre 
of the plastid; in b three inclusions are present; in d the handle of the mirror-shaped plastid 
remained almost colourless, while the rest retained the stain. This form was rare, x 3,000. 
Fig. 5. Longitudinal vertical section through the apex of the thallus of Marchantiapolymorfha, 
showing one apical cell with adjacent tissue and two young ventral scales, a and b , mucilage hairs. 
The chondriosomes in a are delicate rods of varying length ; some of the rods seem to consist of 
I 
