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leaf scar slightly exceeds the vertical diameter. Fig. 1, a b c, illustrates the buds and bud scars of P. tremuloides. The buds are not viscid. The one lettered a is a drawing of a portion of a

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EXPLANATION OF THE FIGURES. FIG. 1.- Populus tremuloides. a, scar and bud near base of branch, enlarged three

diameters; b, natural size near the middle of a rapid growth; c, front and side

view of same enlarged three diameters. FIG. 2.Populus grandidentata. a, enlarged front and side view of bud and scar

near the base of a year's growth; 6, the same farther up the stem; C, enlarged

view near the middle of stem. FIG. 3.— Populus monilifera, a, natural size figure near the middle of a large thrifty stem not far from the base of the growth of last year; the others are taken from near the middle of the same growth. These illustrations and the succeeding ones are all drawn to the same scale, unless otherwise designated.

growth ; b c, views of middle of slender growth; d, view near the base of


Populus grandidentata.In thrifty twigs, one year old, the pith is yellowish white; the wood greenish white. The pith in twigs two or three years old is light brown. The buds are slightly pubescent under a lens and of a grayish-brown color, not viscid, Near the middle of a branch, the leaf scars are about as broad as long. Near the base the transverse diameter is the greater. The internodes of this species in slow or in rapid growth are much longer than those of P. tremuloides. They are often twice as long in stems which have made the same amount of growth. Fig. 2, a b c, illustrates the buds and leaf scars on young stems of P. grandidentata.

Populus monilifera.—The pith is light-brown and a cross section is usually pentagonal. In most slender young branches the pith is green, changing to brown on an exposure of a few minutes to the air. The shape of the leaf scars is about midway between that of P. tremuloides and P. grandidentata. Branches which have made slow growth and the base of thrifty branches are often without angles on the surface. Thrifty young branches have from five to eight prominent vertical ridges. One of these ridges extends below the center of a bud and one runs down from either side of the leaf scar. The branches are of a yellowish or greenish-brown color. There are a few round or oval white or brown spots on thrifty stems a year old. The buds are brown, viscid, not very glossy, and are destitute of pubescence, except a little on the margins of bud scales. The buds are larger but their shape is much the same as those of P. tremuloides. On thrifty branches there are often some buds mixed in with those larger which are short and not fully developed.

For illustrations see Fig. 3, a b c d.

Populus balsamifera.—The young branches are brown and polished. The lower buds of the season are broad and small, and the scar below is broad. The lower buds and leaf scars of these four species of Populus are much alike in shape. The buds on the middle of the thrifty growth of P. balsamifera are quite long, often seven-eighths of an inch. They are curved and pointed, and become viscid. Fig. 4, a b c d e, illustrate buds and leaf scars of this species.

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FIG. 6.
Fig. 4.–Populus balsamifera. a, enlarged view of stem near the lower end; b c,

views of middle of a very slender stem; d e, views of middle of a large growth

of a thrifty stem. Fig. 5.— Juglans nigra. A front and side view of thristy growth near the base; b c, Juglans nigra.—The pith of this species consists of thin plates running transversely, leaving open cavities between them. The pith is of a light-brown color. On a thrifty branch the bud scar is nearly heart-shaped with vertical and transverse diameters about equal. A very small bud can be seen in the sinus of the scar. Above this is a larger bud, most of which is also within the sinus of the leaf scar. Above these buds is a third one, still larger. The transverse diameter of the leaf scar is about equal in length to the distance between the leaf scar and the tip of the upper bud. A side view of the leaf scar shows quite a sharp depression in the middle. On slender branches the bud scars are laterally compressed or appear longer than on stout branches. Fig. 5, a b c d, illustrate this species.

a similar view from a thristy branch near the middle; d, similar views of a

slender stem near the middle or top. FIG. 6.- Juglans cinerea. a, two views of a stem near the base; b c, similar views

near the middle of a branch, d, similar views of slender stems.

Juglans cinerea.—The pith is separated in plates. It is of a dark brown color and in a narrower cavity than that of 7. nigra. The leaf scar on a thrifty growth is not unlike the shape of a sheep's face. The scars left by the woody bundles of the leaf are shown in the drawings of all the species above mentioned. Towards the lower part of a branch, one bud only appears above the leaf scar; farther up on thrifty branches two buds may be seen. The scar is without any sinus or depression at the top. In this species, on the middle of rapid growth, the upper bud is from one-fourth to two-thirds of an inch or even more above the top of the leaf scar. Along the top of the leaf scar is a transverse or curved ridge or crest resembling velvet or plush. This crest is not present in 7. nigra, but is rarely if ever absent in 7. cinerea. The bark on a thrifty branch of 7. nigra when one year old is about a third thicker than that on branches of 7. cinerea of the same age and size. After the first year, and sometimes sooner, the outer bark of 7. nigra cracks and rolls up in scrolls, while the outer bark of 7. cinerea shows nothing of the kind. Fig. 6, a hcd, illustrates this species.

The young trees of these two species of Juglans are not easily distinguished by the leaves. In the axil of the leaf of 7. cinerea, even when quite young, can be seen the velvet ridge. The odors of crushed leaves of the two species are different.

Some observations lead me to believe that many other trees and shrubs can be equally well distinguished by the young naked branches, while in some cases it will be difficult to find good specific characteristics. The drawings for this paper were made by W. Holdsworth.



“And you have walked about-how strange a story!"

In days gone by, a million years or so,
When giant saurians were in all their glory

In the dim twilight of the long ago!
When Hadrosaurus reared his height stupendous,
And Aquilunguine Lælaps leaped tremendous !
Could ye but speak, what stories you could tell us !
How on the oozy


floundered free;
Elasmosaur and all his scaly fellows

That fished and paddled the Cretaceous sea,
And Mosasaurus, how he showed his tushes
Ages ere Moses boated 'mong the rushes!
That “there were giants in those days” is certain,

Not such as those by Scripture story told,
Nor known to us till science raised the curtain,

Their length and breadth and stature to unfold;
Monsters of flesh and bone and horny mail,
And jaws and claws and ponderous length of tail.
Oft have we queried, wherefore had ye birth,

And wherefore sent into a world like this
Ages ere perfect man appeared on earth?

As told in chapter first of Genesis,
Of which our Savans have not yet been able
To show how much is fact, how much is fable !
The “dark idolator of chance" may learn

A lesson pregnant from your gray remains,
See proof of plans, deep-laid, he may not spurn,

By Power Creative, through all time the same;
See glimpses of the slow evolving plan
Developing the monad up to man.
Then hail your advent to the light of day!

A revelation of old time to this,
Along the darkened past a brilliant ray

Lighting an else unfathomable abyss !
And hail to him whose skill your import can make plain,
Can reconstruct the past and make it live again !

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