GAISER: CRYSTALS IN THE SPADIX OF ANTHURIUM = 395 
De la Rue (2) a little later gave further confirmation of 
Rosanoff’s crystals. He reported them in the leaf of Hoya 
carnosa and in the petioles of Pothos crassinervius (Anthurium 
Hookert) and Philodendron pertusum. In his rather crude figure 
(f. 3) of a cell of Hoya carnosa he includes a nucleus and chloro- 
plasts. Rosanoff (17) gives a figure of a cell of Anthurium Selloum 
(f. 4) showing the nucleus lying somewhat beneath the crystal 
and in the conclusion of his paper states that he finds the nucleus 
unaltered in these crystal-bearing cells. Both of these statements 
were made in refuting the statement in an earlier text-book of 
Duchartre (3), ‘“‘ Les celles dans les quelles existent des cristaux 
ne refernment pas d’autres matiéres solides.’’ 
Wittlin (24) has also confirmed Rosanoff. In an extensive 
investigation of various tissues he frequently found the crystal 
with a cellulose sheath accompanied usually by cellulose strands. 
This was the case in the pith of stems of Kerria japonica, in the 
pith of internodes of Caesalpinia Sapan, and Tilia (tissue not 
mentioned). In the fundamental tissue of stems and petioles 
of Philodendron pertusum (Monstera deliciosa) and P. “‘argyrea’’, 
and Morus alba (tissue also not mentioned), the strands were 
found to be very short and broad or lacking altogether. For his 
study he used fresh material and cut successive sections from the 
gcowing point backward. In younger regions of stems of Kerria 
jtponica, about 1.5 mm. in thickness, he found the crystal lying in 
t’ eplasma with the nucleusalso visible. Cutting further he found 
successively larger crystals in cells whose plasma with the 
nucleus was contracted about the crystal, until in stems 2.5 mm. 
thick he found the crystals touching the cell wall. At this late 
stage in development the formation of the cellulose membrane 
about the crystal occurs, beginning at the point of contact 
of the crystal with the cell wall. With the growth of the 
-ell a so-called foot is formed, which broadens and becomes 
stretched into a strand that pushes the crystal with its sheath 
towards the center of the cell. The plasma is partly used and 
partly displaced. The nucleus becomes invisible at the first 
appearance of the cellulose strands (24, pl. 1, f. 1-4). In Cae- 
salpinia Sapan similar appearances were found although the 
elaioplasts and plasma persist after the nucleus becomes in- 
visible. The presence of the nucleus in cells containing small 
crystals and its later disappearance he regards as constant. 
