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London, 1914. 
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Zool. Bot. Ver. Wien. 1890. 125-138. 
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EXPLANATION OF PLATES XV-XXVIII 
A, aerenchyma; B, bast; C, collenchyma; CM, cambium; CK, cork; EN, endodermis; 
EP, epidermis; P, parenchyma; PH, phloem; RC, resin canal; SC, sclerenchyma ; RH, root 
hair; T, tracheae; X, xylem; PX, protoxylem; MX, metaxylem; WF, wood fibers; WP, 
wood parenchyma; WR, wood rays; VB, vascular bundle. 
The figures were made with the aid of a camera lucida. The compound microscope 
was a Spencer, Oculars 5X and 10 X and objectives 4 and 16, with a standard tube length, 
were used in various combinations. 
Plate XV 
Subterranean Systems of Water Plants 
Fig. a. Polygonum Muhlenbergii. 
Fig. b. Phragmites communis. 
Fig. c. Scirpus fluviatilis. 
Fig. d. Typha latifolia. 
Fig. e. Iris versicolor. 
Fig. /. Sagittaria latifolia. 
Fig. g. Scirpus validus. 
Fig. h. Spartina Michauxiana. 
Plate XVI 
Fig. i. Typha latifolia, rhizome, X 75. 
Fig. 2. Typha latifolia, root, X 93. 
Plate XVII 
Fig. I. Phragmites communis, rhizome, X 150. 
Fig. 2. Phragmites communis, root, X 115. 
Plate XVIII 
Fig. I. Spartina Michauxiana, rhizome, X 125. 
Fig. 2, Panicum virgatum, rhizome, X 102. 
Plate XIX 
Fig. I. Iris versicolor, rhizome, X 50. 
Fig. 2. Iris versicolor, root, X 75. 
Fig. 3. Scirpus fluviatilis, rhizome, X 50. 
