APPENDIX G. BOTANY. 



293 



Plate XVIII. Abronia cycloptera. 



Fig. ] , involucre, somewhat magnified-, fig. 2, fruit of the natural size ; fig. 

 3, transverse section of the fruit, magnified ; fig. 4, an achenium, magni- 

 fied ; fig. 5, transverse section of the same, also magnified ; fig. 6, the 

 embryo. 



Plate XIX. POA 1NTERRUPTA. 



Fig. 1, a spikelet ; fig. 2, single flower; fig. 3, a caryopsis — all magnified. 



Plate XX. Uniola stricta. 



Fig. 1, a spikelet, magnified. 



