THE WANDERING TAPETAL NUCLEI OF ARISAEMA 469 
The tapetal nuclei for a considerable period show peculiarities of 
structure, and take on amoeboid forms suggestive of active migration 
among the developing pollen spores. 
Washington State College, 
Pullman, Wash. 
Literature 
Inasmuch as the material presented above is intended merely 
to report observations of fact without going into any discussion of 
their possible bearing upon development or possible relationship of 
the species studied, only such literature has been cited as may help 
to make clear the findings reported. For a more complete bibliog- 
raphy see Juel's work. 
Hannig. Uber die Bedeutung der Periplasmodien. III. Kritisch'e Untersuchungen 
iiber das Vorkommen und die Bedeutung von Tapeten und Periplasmodien. 
Flora, 102: 335-382. 191 1. 
Juel. Untersuchungen iiber die Auflosung der Tapetenzellen in den Pollensacken 
der Angiospermen. Jahrb. wiss. Bot. 56: 337-363. 1915. 
Pickett. A Contribution to Our Knowledge of Arisaema Iriphyllum. Mem. Torrey 
Club. 16: 1-55. 1915. 
EXPLANATION OF PLATE XX. 
Fig. I. A section showing the periplasm with tapetal nuclei among the spore 
tetrads. X 375- 
Fig. 2. A similar view from a section of an older anther, showing tapetal nuclei 
in periplasm among spores with well developed exine. X 375- 
