CONTENTS. 
PAGE. 
1. REPORTS FOR THE YEAR 1910:— 
a. Report of the Officers of the Board................00. 7 
b. Twenty-second Annual Report of the Director......... 14 
' 2. SCIENTIFIC PAPERS:— 
a. Illustrated studies in the genus Opuntia—IV.— 
SOM SAE CPENUAS io ss cco sak seechcdcha seen 25 
b. The Agaves of Lower California. — 
Fea T YT CIOR OE 50S ot vee cs heeginy teh enis 87 
ec. Crataegus in Missouri—II.— 
Bee GO. GONE. eas s cine caeevsd Ce 67 
d. Revision of the Agaves of the Group Applanatae. — 
pe Wotan Trelease .. :.... sos ee 85 
e. A dwarf form of Agave angustifolia, — 
Dy wim Trelease. ... .. 2: issseem ewes. 99 
Jf. An additional tree-yucca and one other species new to 
the United States. — 
AAA WESOOOE. TPOMESE. 6... kc cesvscba scan ean. 101 
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