PLATE 3 
Pollen-mother-cells of some polyploidous rubi : a 
A. — Rubus strigosus. Horticultural variety Ranere, diploid. 
B. — Rubus idaeus (?), Horticultural variety La France, tetraploid. 
C. — Rubus idaeus (?) Xstrigosus. Horticultural variety La France X Ranere, triploid. 
D. —Rubus strigosus X idaeus , (?). Horticultural variety Erskine, triploid. 
E. —A tetraploid Rubus, Merveille de Rouge. 
F. —A tetraploid Rubus, Merveille de Quatre Saisons Rouge. 
G. H and I.—Three stages in the heterotypic division of Surpasse Merveille a blanc. 
J, K and L—Three stages in the heterotypic division of the Ness, a tetraploid rasp¬ 
berry-blackberry hybrid. 
a Drawings reduced one-half. 
