Between Drosera filiformis mid D. interjnedia. 95 



are on the average ^ inch across, though they vary more than 

 do those of the other parent. They are of a purple-pink hue. 

 The petals of D. intermedia are 3^ inch across and of a pure 

 white color. Those of the hybrid seem decidedly to approach 

 the latter, since the flowers are ^ inch across, and are white 

 with a faintly recognizable pink flush. 



(/) Floral Structure. — The sepals form an exceptionally in- 

 teresting study. Those of D. filiformis are abundantly covered 

 externally with glandular hairs (Plate XII, Fig. 70) which vary 

 greatly in structure and length. They may be from 180-380 // 

 long. Generally it may be said that all of them end in a flat- 

 topped mass of 4-12 glandular cells, but the stalk supporting 

 these may be a single cell row or two rows below gradu- 

 ally running into one or two rows above. Each stalk also con- 

 sists of 3-6 or 7 tiers of elongated cells. In the distal hairs 

 of each sepal spiral tracheae may enter the base of the 

 hair and soon end blindly, or may be prolonged about one- 

 third the length of the hair. Rosette-shaped, four-celled, 

 sessile glands, and toward the base of the sepals two-celled 

 glands of similar appearance, are also disposed over the 

 exterior. Stomata are abundant, are nearly circular in out- 

 line and measure 30 X 28 fi. The internal (upper) epidermis is 

 glabrous, and consists, like the upper epidermis, of very 

 variable cells, alike in size and shape. In D. intermedia the 

 outer surface of each sepal is glabrous, but a moderate num- 

 ber of two-celled glands on a slight stalk cell, as well as 

 stomata, occur over its surface. In D. hybrida, the outer surface 

 of each sepal bears the same type of stalked gland hair as is 

 seen in D. filiformis (Fig. yb), but here they are on the average 

 only one-third to one-fourth the length of those on the parent 

 species. But, like the parent, they vary in structure amongst 

 themselves. Beside these are the four-celled sessile glands, 

 which differ in no way as to size from the parent, each being 

 30 // across. They are more scarce, however, than in the 

 parent. We thus have the interesting case shown of one type 



