164 
EXPLANATION OF THE PLATES, 
Plate VI. HORKELIA TRIDENTATA.— Page 84. 
AN ENTIRE PLANT OF TIIE NATURAL SIZE. 
Fig. 1. Aii expanded flower and two buds ; enlarged. 
2. The flower laid open ; a little more enlarged. 
3. A petal ; magnified. 
4. A stamen ; more magnified. 
5. The head of pistils. 
6. An aclienium, with its persistent style. 
Plate VII. WHIPI’LEA MODESTA. — Page 90. 
AN ENTIRE PLANT OF THE NATURAL SIZE. 
Fig. 1. A separate flower; moderately enlarged. 
2. A sepal; and, 
3. A petal; both a little more enlarged. 
4. Front view of a stamen. 
5. Back view of the same; equally magnified. 
G. Pistil, transversely divided ; more magnified. 
7. An ovule ; more magnified. 
8. A flower, longitudinally divided ; considerably.magnificd. 
9. Plan of the flower. 
Plate VIII. CORNUS SESSILIS.— Page 94. 
A BRANCH OF TIIE NATURAL SIZE. 
Fig. 1. Umbel of flowers and involucre. 
2. The involucre ; shown separately. 
3. An exterior leaf of the same. 
4. Interior leaf of the same. 
5. A separate flower. 
G. The same, with two of the petals and stamens removed to show the teeth of the calyx. 
7. The fruit. 
Plate IX. HOFMEISTERIA PLURISETA.— Page 96. 
A PLANT OF THE NATURAL SIZE. 
Fig. 1. A separate flower ; enlarged. 
2. The corolla of the same laid open ; more magnified. 
3. A stamen ; still more magnified. 
4. Two paleaa and a hair of the pappus ; more magnified. 
5. An aclienium, crowned with its pappus ; considerably magnified. 
G. Involucre and receptacle ; moderately magnified. 
Plate X. ASTER BIGELOVII.— Page 97. 
UPPER PORTION OF TIIE PLANT OF TIIE NATURAL SIZE. 
Fig. 1. A ray_flower. 
2. A branch of the style from the same. 
3. A disk flower. 
4. A separate stamen from the same. 
5. Style and its branches, from a disk flower. 
G. An aclienium. 
7. A hair of the pappus ; high]} magnified. 
