472 



THE ERICALES 



extend far out, furnishing a natural landing place for hovering 

 animals as moths and humming birds. In this position the 

 spores cannot be sifted out and we find them fastened together 

 in fours, just as they were formed in the mother cell, by sticky 

 threads which cause them to adhere on the insect's body in 

 fringe-like masses (Fig. 327, G). One of the lower basidiomy- 

 cetes (Exobasidium) infests the leaves and flowers of the azalea 

 and other genera, causing large watery outgrowths that are 



FIG. 327. Common forms of Ericales: A, Indian pipe (Monotropo). 

 Leaves reduced to scales and without chlorophyll, owing to saprophytic 

 habit of plant. B, section of flowers, showing polypetalous corolla. C, 

 inflorescence of the blueberry (Vaccinium). D, section of flower, showing 

 sympetalous corolla and epigynous type of flower. E, a stamen enlarged, 

 opening by pores at end of anther. F, Azalea, showing irregular type of flower. 

 G, spores attached by viscid threads. 



often eaten under the impression that they are the fruit of the 

 plant. The members of this order are adapted to a wide range 

 of conditions though more characteristic of north temperate and 



