HYBRID DROSERA. 245 
large intercellular spaces. Subjacent are four to five sclerenchyma layers 
considerably less thickened than in D. filiformis, but which have, as in 
it, the most highly thickened zone in the middle of the mass. The 
average thickness of the thickest wall is 4°5 p. 
The fascicular system will not now be treated of, as equally in 
parents and hybrid it is complicated in arrangement. 
(c) Inflorescence.—The scorpioid cyme of D. filiformis is, from the 
bud state onward, semi-erect, and the flowers are closely crowded along 
the false axis, against which they are closely adpressed. The number of 
flowers in an inflorescence averages 14. The cyme of D. intermedia is 
closely coiled in the young state, the component blooms are somewhat 
loosely arranged: they spread out in radiate fashion from the false axis, 
and the average number of flowers is 8. The cyme of D. hybrida is 
rather strongly incoiled, as in the latter parent. The blooms average 10, 
and these are set in a rather scattered sub-secund manner along the false 
axis. 
(d) Period of Blooming.—In my paper on “Plant Hybrids’”* I 
advanced a considerable body of facts to prove that the flowering period 
of many hybrids is very exactly intermediate between the periods of the 
parents, while other hybrids show a decided divergence toward one 
parent. It has not been possible to do more in the present study than to 
ascertain approximately the relative period of blooming. From a study 
made at several localities in New Jersey during the past season, it was 
learned that the first blooms of D. filiformis opened on June 7-10, and 
by June 28 the terminal flowers of the cyme were open. When collected 
on June 30a number of the lower flowers on the more vigorous hybrid 
plants had already passed, while the lowest flowers on small plants and 
the lower middle flowers on strong plants were fully open. The plants 
continued to flower in the University greenhouses till August3. As already 
noted, when piants of D. intermedia were gathered the involute flower 
stalks were just unrolling, and later observation showed that this species 
begins to bloom about July 3, and continues until about August 15. In 
attempting to account for the origin of the patch of hybrid plants, there- 
fore, it seems extremely likely that a late bloom of D. filiformis and an 
early bloom of D. intermedia had been concerned in the pollination pro- 
cess. The limited observations just recorded point to D. hybrida as a 
form which blooms at a period between those for the parent species. It 
should be said, however, that the writer and another member of the 
party succeeded in obtaining some four blooms of D. filiformis on as 
many plants as late as August 10. That they were entirely out of season 
was proved by hundreds of surrounding plants having their capsules in 
an advanced state of maturity. 
(e) Size and Colour of the Blooms.—Those of D. filiformis 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 | inch across and of a pure white colour. Those of the hybrid seem 
decidedly to approach the latter, since the flowers are 2 inch across, and 
re white with a faintly recognisable pink flush. 
(f) Floral Structure.—The sepals form an exceptionally interesting 
* Trans. Roy. Soc. Edin. vol. xxxviii. 
