370 BOTANICAL GAZETTE [MAY 
' enlarged, chloroplasts reduced in size, often a more abundant 
protoplasm than normally, and variations in the calcium oxalate 
content. In some fungous galls GUTTENBERG (24) found a tendency 
for the nucleus to become lobed, to divide amitotically, to decrease 
in size, and to force the chromatin toward the periphery. The 
cytologic features of some gall tissues, resulting from insect inva- 
- sion, has also been described by MoLiiArp (49). The nuclei show 
a decided tendency toward amitotic division, which often results 
in the presence of several nuclei in a cell, with no formation of new 
walls. The nucleoli as well as the nuclei become greatly hyper- 
trophied, and the former may be divided often without the subse- 
quent division of the nucleus. At times the nucleus multiplies by a 
method of budding in addition to the more common means of 
abstriction. The nuclear membrane may finally disappear, and 
eventually even the nucleoli may become disintegrated. HoUARD 
(29) reported similar hypertrophy of the cell organs of the flowers 
of Teucrium when attacked by the larvae of Copium. PERCIVAL 
(645) described the effect of Synchytrium in the potato “wart 
disease’? upon the host cells. These enlarge, the cytoplasm in- 
creases, and the nucleus becomes deformed. ‘‘The organisms 
stimulate the invaded cells and at the same time appear to stimu- 
late division and growth in the adjoining cells.”’ Changes in root 
cells have been noted from time to time, especially in the studies 
on mycorhizae. Macnus (41) found the nucleus modified in these 
symbiotic structures. SHIBATA (68) notes that the nuclei in such 
conditions become enlarged, amoeboid, and divide amitotically. 
They may be strongly colored at first, but later they seem to 
become normal as regards division and color. ZacH (94)) describes 
the following cytological changes in cycad root cells due to fungous 
invasion. The nucleus becomes amoeboid or otherwise misshapen, 
the starch is dissolved away, the calcium oxalate increases in 
amount, and finally nucleus and plasm die. The cells of the grow- 
ing point and the Anabaena region are not seriously invaded. 
MOLLIARD (52) reported that the nematode worm lives in a tissue 
which has giant cells with numerous nuclei and enlarged nucleoli. 
VUILLEMIN and LEGRAIN (82) reported various nuclear phenomena 
caused by the same worm in symbiotic relationship with the roots 
