554 A TEXTBOOK OF BOTANY [Cn. XII\ 



Cranberry, Blueberry, and Bearberry. Here also are in- 

 cluded two families having special ecological interest, viz. 

 the saprophytic Indian Pipe, or Ghost Plant (Fig. 60), 

 and the Pyxie, or Flowering Moss, which has adopted the 

 moss habit. 



ORDER 26. PRIMULALES: THE PRIMROSES AND KIN. 

 Some 1100 species, many tropical, with prominent flowers 

 distinguished by the position of the five stamens opposite the^ 

 Jobes of the corolla (Fig. 201). They include all of our true 

 Primroses (not Evening Primroses), with Cyclamen, and 

 the Leadwort of greenhouses. 



ORDER 27. E BEN ALES: THE EBONY AND KIN. Some 

 1000 species, mostly tropical, of trees and shrubs, noted for 

 their hard and valuable woods, typified by Ebony. The 

 Persimmon also belongs here, and our garden Silver Bell. 



ORDER 28. GENTIANALES (CONTORTS) : THE GENTIANS 

 AND KIN. Some 4400 species of widely-spread trees, shrubs, 

 and herbs. Here belongs the important Olive family, with 

 its flowers on the unusual plan of four, including such im- 

 portant plants as the Olive, Ash, Fringe Tree, Golden 

 Bell, Jessamine, Privet, and Lilac. Related is the tree 

 which produces the poison strychnine. Here belong, of 

 course, the Gentians, and also the Dogbanes, with Oleander 

 and Periwinkle. Related are the Milkweeds, with their 

 milky juice, their very remarkable diversity of form and 

 habit, and the high specialization of their flowers in connec- 

 tion with pollination. 



ORDER 29. TUBIFLORM: THE TUBULAR-FLOWERED FAMILIES. 

 A great assemblage, some 13,500 species, of trees, shrubs, 

 and herbs, having in common an elongated corolla tube 

 bearing the stamens, the ovary being superior in some, 

 inferior in others. They include the Morning Glory family 

 (Convolvulacece), with Morning Glory, Sweet Potato, and 

 the parasitic Dodder (Fig. 59) ; the Phloxes ; the Borage 



