Cc. A. BARBER. 17% 
lignified cells appears in the folds of haustoria clasping the 
roots of Commelina fruticosa, it is present.in most if not all 
of the dozen or so examined which were attached to Hemi- 
desmus indicus and Capparis horrida, 
12. Crystals of Calcium Carbonate.— As has been pointed 
out by Edelhoff* and Valeton; there are no calcium oxalate 
crystals in the tissues of Cansjera, their place being taken 
by crystalline cystoliths of calcium carbonate. Masses of cal 
clum carbonate crystals, although rare in young haustoria, 
are abundant in older ones, being presumably only formed 
in cells whose activity 1s onthe wane. Thus, certain tracts 
of cells which are no longer required by the haustorium are 
noted for their frequent appearance. The crystals occur in 
the elongating portion of the inner cortex, inside the collapsed 
layers near the lacunar tissue, in the cortex outside the collapsed 
layers and, especially, in the ground tissue immediately above 
the nucleus (Plates VI, IX and XI). They are rarer in the 
hypoderm and are not formed in the nuclear tissues. The dis- 
tribution of these crystal masses is thus mainly cortical, and 
follows with remarkable fidelity that of the calcium oxalate 
crystals in the haustoria of Olax scandens (Olax, para. 16). The 
presence of these bodies has been noted in some forty haus- 
toria, but was probably more widely spread in the original 
material because many of the sections were mounted in dilute 
glycerine and lay for some time before examination. In some 
sections, at least, the crystals have been noted gradually to 
disappear in this medium. In these cases no definite structure 
was left behind and no residual basis has been found giving 
callose reactions (see Plate VI, fig. 2, x, and the description of 
this figure). Fresh material has not been available for the 
examination of these bodies, but, from the spirit material at 
* Edelhoff, E., Vergl. Anat. des Blattes der Familie der Olacineen. Engler, Botan, 
Jahrb, VIIT, 1886-7. 
+ Valeton, Crit. Overz. d, Olacincen, Groeningen, 1886. (1 have not been able to see this 
paper. ) 
