APPENDIX I 3859 
Fig. 8. Head of Yarrow. 
A, top view (magnified); B, lengthwise section (magnified). re, re- 
ceptacle; i, involucre; r, ray-flowers; d, disk-flowers; c¢, corolla; 
s, stigma; ch, chaff, or bracts of receptacle. 
Fic. 9. A, Panicle of Oat; B, Compound Umbel of Carrot. 
