Memoir Volume 1-11 (Paperback)

This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1913 edition. Excerpt: ...with the following results: TABLE 24. Area Of Vein Islets In A Series Of Immature Leaves Taken In Order From The Tips Of The Shoots Backward, From Vitis Vulpina Twenty-five And Ten Years Of Age That this was an entirely typical condition has been shown by many field counts of veinlet intersections by a method explained later (page 317). The sizes of the vein islets in the immature leaves on the cuttings as given in table 23 offer evidence to the same effect. If the midrib be called the primary vein, its chief branches secondary veins, the main branches of the secondary veins tertiary, and so on, the final most minute veinlets may be given a definite rank. A comparison of the rank of t.hc veinlets in leaves borne by cuttings of Vitis vulpina of different ages shows the following results: TABLE 25. Rank Of Veinlets In Immature Leaves Borne By Cuttings Of Vitis Vulpina Of Different Ages The important fact is evident from table 25 that in the leaf from the older vine the vein islets have been divided by the development of an additional rank of veinlets, and each division has been partly penetrated by veinlets of still higher rank. The fact that size relationship of the vein islets holds for the immature leaves of old and young vines as definitely as it does for the mature ones, which have been subjected to the various external factors of environment, is further evidence of importance supporting the claim that the difference in size of the vein islets is due to a constitutional rather than to an environmental cause. In May, 1910, another set of cuttings was started, this time in prepared soil. These cuttings were obtained and started for the writer by an assistant, and the grouping was somewhat different from that used in the first series. All...