IN VEGETABLE BIOLOGT. 621 



Fig. 60. Junction of three long cells of Chylocladia articulata. The protoplasm 

 has collected at the top of one of them, x 600. 



61. Halurus equisetifolius. Meeting-point of two young cells. A dense 



layer of protoplasm lines the intercellular wall at each side. X 140. 



62. Two axial cells of Ceramium rubrum. The protoplasm runs in the 



lorm of a hollow tube from stopper to stopper. X 140. 



Studies in Vegetable Biology.— II. On Rosanoff's Crystals 

 m the Endosperm-Cells of ILanihot Qlaziovii, Mull. Arg. 

 By Spenceb Le M. Moore, F.L.S. 



[Eead 2nd April, 1885.] 



The existence of crystals fixed to the wall of their containing-cell 

 and themselves enclosed in an investment of cellulose appears to 

 have been first noticed by Sehacht * who described in some 

 detail the large single crystals found in the leaves of Citrus 

 vulgaris. A few years afterwards Bosanoff f wrote his well-known 

 memoir on the Crystal-masses in the pith of Kerria japonica and 

 Ricinus communis, and in the petiole of several Aroidese and the 

 floral organs of JEncephalartos and Nelumbium ; he showed that 

 the crystals are either directly fixed to the wall of the cell and 

 surrounded by a cellulose investment, or, still retaining the in- 

 vestment, are pedicellate upon the wall. Similar crystals were 

 found by De La Rue J in the leaves of Soya carnosa. Pfitzer§, 

 working over Schacht's ground, very elaborately monographed 

 the crystals of Citrus which he found not in the leaves alone, but 

 in their stalks and in the stem : he further proved that they are 

 not, as Sehacht had supposed, of sulphate, but of oxalate of lime ; 

 and he made a careful microchemical investigation of the sup- 

 porting pedicels. He also discovered that at an early stage the 

 crystal can be seen lying freely in its ceil surrounded by a nimbus 

 of protoplasm. Besides this, Pfitzer showed that the crystals 

 met with in the cortical parenchyma of Salix aurita, Populus 

 ttalica, and other trees are secured to their cell-wall by thick depo- 

 sits of cellulose. Poulsen || subsequently wrote a paper on the 

 pedicellate sphere-crystals surrounded by cellulose of Rose-berries ; 



* Abliand. Senck. Gesell. z. Frankfurt, i. 



t Ujt. Zeit. I860 and 1867 



t Bot. Zeit. 1869. 



§ ' Flora,' 1872. A short account of the crystals is given by Dc Bary in his 

 ' Vergleichende Anatomie ' (p. 147). 



II Vidensk. Medd. Naturhist. For. Kiobenhavn, 1874. 

 LINN. JOUHN. — BOTANY, VOL. XXI. 2 z 



