oak raised in 1840 from a tree at Woburn Abbey. Measurements show that the former was 6 ft. 7 in. in girth in 1865, and is now 9g ft. 4 in.; whilst the latter, only 1 ft. 8 in. in 1865, is now 8 ft. 7 in. Mr. J. Hopkinson in Trans. Hertfordshire Nat. Hist. Soc. xii. pp. 249, 250, gives diagrams showing the comparative annual increase during two periods of these trees. I may add that the habit of the two trees differs but little, and the soil is more suitable to the sessile oak.
Mr. Sharpe,’ forester at Monreith, where Sir Herbert Maxwell planted in 1898 a quantity of oaks of the two species, on a fairly deep loam soil, measured ten of each sort in 1905, and informs us that the sessile oak averaged 134 feet in height, and the pedunculate oak only 10½ feet. (H.J.E.)
QUERCUS SESSILIFLORA, Sessile or Durmast Oak
- Quercus sessiliflora, Salisbury, Prod. Stirp. Hort. Chap. Allerton, 392 (1796); Loudon, Arb. et Frut. Brit. iii. 1736 (1838); Boswell Syme, Eng. Bot. viii. 157, tab. 1289 (1868).
- Quercus sessilis, Ehrhart, Beiträge, v. 161 (1790).
- Quercus Robur, Miller, Gard. Dict., vii. t (1759).
- Quercus Robur, Linnæus, var. β; Mantissa, 496 (1771).
- Quercus Robur, L., sub-species sessiliflora, DC. Prod. xvi. 2, p. 6 (1864).
- Quercus Robur, L., var. sessiliflora, Hooker, Stud. Flora Brit. Isles, ed. 2, 364 (1878).
A tree resembling Q. pedunculata, but with more regular branching, resulting in a denser crown of foliage. It differs somewhat in the characters of the branchlets, buds, leaves, pistillate flowers, and fruit, as follows:—
Branchlets pubescent, especially near the top. Buds more sharply pointed, with scales pubescent on the outer surface, especially near the apex, and having long marginal cilia.
Leaves with a long petiole; symmetrical, obovate-oblong, widest at the middle and gradually diminishing to the base, which is cuneate and generally without auricles; firm, almost coriaceous in texture; sinuately lobed or pinnatipartite, the lobes being oblong or triangular, entire, occasionally apiculate ; upper surface glabrous and shining, dark green ; lower surface brighter even glaucous green and always more or less pubescent. Lateral nerves running to the sinuses are very seldom present. Pistillate flowers with stigmas almost sessile. Fruit solitary or crowded, inserted on the branchlets, or borne sessile on an erect, stout, short pubescent peduncle. Cups pubescent, with scales more numerous and more closely crowded together than in Q. pedunculata.
This species is quite distinct from Q. pedunculata, and the characters given above are very constant. The pubescence, which is visible in this species throughout, on the top of the twigs, buds, stalks, peduncles, cups, and under surface of the leaves, is not so pronounced in specimens occurring in rainy districts ; but it can always be made out by a lens. The physiological differences are well marked. The sessile
1 Cf, Sir Herbert Maxwell’s account in Gard. Chron. xxxvii. 82 (1905).
