ECOLOGY OF FLOWERS 361 
magnified view of the hairs from the outer surface of 
mullein petals, shown in Fig. 253.1 
Sometimes the recurved petals or divisions of the corolla 
stand in the way of creeping insects. In other cases the 
Fic. 253. — Branching Hairs from the Outside of the Corolla of the Common 
Mullein. (Magnified.) dr, a gland. 
Fic. 254.— A Sphinx Moth, with a Long Sucking-Tube. 
throat of the corolla is much narrowed or closed by hairs, 
or by appendages. Those flowers which have one or more 
1 On protection of pollen, see Kerner and Oliver, Vol. H, pp. 95-109. 
