AND AMERICAN RURAL SPORTS. 85 
that the entrance of man into the planet is, comparatively 
speaking, of extremely modern date, and that the effects of 
his agency are only beginning to be felt. 
A modern writer has estimated, that there are in Ame- 
rica upwards of four millions square miles of useful soil, 
each capable of supporting two hundred persons; and 
nearly six million, each mile capable of supporting four 
hundred and ninety persons. If this conjecture be true, 
it will follow, as that author observes, that if the natural 
resources of America were fully developed, it would afford 
sustenance to five times as great a number of inhabitants 
as the entire mass of human beings existing at present upon 
the globe. The new continent, he thinks, though less 
than half the size of the old, contains an equal quantity: of - 
useful soil, and much more than an equal amount of produc- 
tive power. Be this as it may, we may safely conclude that 
theamount of human population now existing, constitutes but 
a small proportion of that which the globe is capable of 
supporting, or which it is destined to sustain at no distant 
period, by the rapid progress of society, especially in 
America, Australia, and certain parts of the old continent. 
[Lyell’s Geology. 
MARYLAND YELLOW-THROAT. 
SYLVIA MARILANDICA. 
[Plate VIII. Vol. 2. Size of life. ] 
Turdus Trichas, Linn. Syst. 1. 293.—Epw. 237.— 
Vellow-breasted Warbler, Arct. Zool. 11.Nq. 283. Id. 
284.—Le Figuier aux joues noires, Burr. vy. 292.— 
La Fauvette a poitrine jaune de la Louisiane, Burr. 
y. 162. Pl. Enl. 709, fig. 2.—Latru. Syn. 1v.—J. 
Doveuty’s Collection. 
Tuts is one of the humble inhabitants of briars, bram- 
bles, alder bushes, and such shrubbery as grow most luxu- 
riantly in low watery situations, and might with propriety 
be denominated Humility, its business or ambition seldom 
leading it higher than the tops of the underwood. Insects 
and their larve are its usual food. It divesinto the deep- 
est of the thicket, rambles among the roots, searches round 
the stems, examines both sides of the leaf, raising itself on 
its legs so as to peep into every crevice; amusing itself at 
times with a very simple, and not disagreeable, song or 
twitter, whitititee, whitititee, whitititee; pausing for half 
a minute or so, and then repeating its notes as before. It 
inhabits the whole United States from Maine to Florida, 
and also Louisiana; and is particularly numerous in the 
low swampy thickets of Maryland, Pennsylvania, and 
New-Jersey. It is by no means shy; but seems delibe- 
rate and unsuspicious, as if the places it frequented, or its 
own diminutiveness, were its sufficient security. It often 
visits the fields of growing rye, wheat, barley, &c. and no 
doubt performs the part of a friend to the farmer, in rid- 
ding the stalks of vermin, that might otherwise lay waste 
his fields. It seldom approaches the farm-house or city; 
but lives in obscurity and peace amidst his favourite thick- 
ets. It arrives in Pennsylvania about the middle or last 
week of April, and begins to build its nest about the mid- 
dle of May: this is fixed on the ground, among the dried 
leaves, in the very depth of a thicket of briars, sometimes 
arched over, and a small hole left for entrance; the mate- 
rials are dry leaves and fine grass, lined with coarse hair; 
the eggs are five, white, or semi-transparent, marked with 
specks of reddish-brown. The young leave the nest about 
the twenty-second of June, and a second brood is often 
raised in the same season. Early in September they leave 
us, returning to the south. 
This pretty little species is four inches and three-quar- 
ters long, and six inches and a quarter in extent; back, 
wings, and tail, green-olive, which also covers the upper 
part of the neck, but approaches to cinereous on the crown; 
the eyes are inserted ina band of black, which passes from 
the front, on both sides, reaching half way down the neck; 
this is bounded above by another band of white deepening 
into light blue; throat, breast, and vent brilliant yellow; 
belly, a fainter tinge of the same colour; inside coverts of 
the wings also yellow; tips and inner vanes of the wings, 
dusky brown; tail cuneiform, dusky, edged with olive- 
green: bill black, straight, slender, of the true Motacilla 
form; though the bird itself was considered as a species of 
Thrush by Linnzus, but very properly removed to the 
genus Motacilla by Gmelin; legs flesh-coloured; iris of the 
eye dark hazel. The female wants the black band through 
the eye, has the bill brown, and the throat of a much paler 
yellow. This last, I have good reason to suspect, has 
been described by Europeans asa separate species; and that 
from Louisiana, referred to in the synonymes, appears evi- 
dently the same as the former, the chief difference, ac- 
cording to Buffon, being in its wedged tail, which is 
likewise the true form of our own species; so that this 
error corrected will abridge the European nomenclature 
of two species. 
The chief difference between the male and female, in the 
markings of their plumage, is, that the female is destitute 
of the black bar through the eyes, and the bordering one of 
pale bluish-white.—Wrtson. 
