PLATE X. 
Fic. 1.— TRANSVERSE SECTION OF LEAF of pampas-grass (Gyne- 
rium argenteum), San Francisco, 1882, magnified 40 diameters by 
Collins’s one-inch objective; mounted in glycerine; no beliostat. 
Fig. 2. — TRANSVERSE SECTION OF LEAF of pine, San Fran- 
cisco, 1882, magnified 40 diameters by Collins’s one-inch objective; 
no heliostat. 
