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another brood ready for his care; thus all the season is occupied by them in building nests, in incubation, and in rearing their young, until the moulting season arrives, which is about the twenty-fifth of August. The pigeon family breed in a similar manner, except that the young are fed from the crop of the male, and it is truly a greater wonder in nature, that there should exist a sympathy between the male pigeon and his offspring, and that at their appearance his crop should undergo so great a change. The rapacious birds return annually to their old nests, and by repairing them, make them suitable receptacles for their eggs. There is an unfitness in the structure of birds of prey which makes it inconvenient for them to build a nest with the facility of some other families of birds. The white-headed eagle selects some dead branch of a tree, and by hooking her bill on it, with her weight breaks it off. In its descent, she swoops and grasping it with her claws carries it away to make her nest; she pounces upon bunches of hay, sods of earth or any heap of rubbish, and carries it to the already accumulated heap of such substances. There is no artistic skill displayed in its construction; the top of it is merely a horizontal plane, with a shallow cavity to receive her eggs. Some families in this order of birds build better nests, but they show the same unhandy and awkward way in doing it, and there are some species of other families in this order which build no nest.
There are other birds, also, such as the swallows, whose forms are ill-adapted for good nest builders; with small feet and short weak legs it is toilsome for them to gather material for a nest from off the ground. Now observe all those birds whose structure is similar to that of the swallow family. Not one species of the family Caprimulgidæ builds a nest. The whippoorwill lays her eggs on the ground in the woods : the night-hawk on the naked rock, or the bare ground in open pastures. Look at the belted kingfisher, whose form is similar to the above mentioned birds; how ill-adapted he is to gather materials from the ground to form a nest. Although a bird of strong pinion, yet deprive him of the use of his wings, and place him on the land, and he is almost helpless.
In the different species of the Picidæ, or Woodpecker family, are as many instances that the structure of birds determine whether those of certain forms build a nest or not, and if they do, they return to it annually to render it fit for a home for themselves and family during the breeding
It is a tedious task for the chimney swallow to procure the material for its nest; it requires energy, skill and strength to perform the work. Flying with force, they grasp the point of the twig with their bill, and often try several times before they succeed in breaking it off. The female visits her former breeding place, and examines her nest; if it needs repairs, she adds more twigs and gum to it, and it is all right again. Thirty years ago this species of swallow was rarely found breeding in Essex County; now many pairs breed in almost every village where they find an unoccupied chimney.
The Chimney Swallow (Cypselus pelasgius) does not possess the easy and graceful motion when on the wing that is shown by the Barn Swallow (Hirundo rustica) in his flight, but moving more swiftly and vigorously, they must destroy an innumerable number of insects in a season. It not unfrequently happens that their nest is dislodged from its place, and falls in consequence of rain or damp weather. When such accidents happen, the whole brood is precipitated to the bottom of the chimney. If its members are of sufficient age and strength, they will climb up again and remain clinging to its sides, until fledged and able to care for themselves.
There are occurrences happening to them which are of greater moment. Sometimes having selected a flue in the chimney leading to the bedroom, and having there brought forth their numerous young, and their cares consequently increasing so as to require their labors in the night, the rushing whirring noise of their flight as they pass up and down the flue may so disturb the nervous sleeper that he is determined to be rid of such an annoyance; he accordingly prepares in the habitation of these birds a fire of straw; the parents of the unfledged young flee in dismay, and rise above their smoking tenement and wheel about in terror, then dive down near its top as though they would rescue their suffocating brood from a death so awful. At last their courage gone they turn and soar away above the scene, while their young drop one by one in the fire below, and the parental feelings of the old birds induce them to linger about their desolate home for many days. To obviate this inhuman practice, a board placed on the top of the chimney before they commence breeding is all that is necessary.
THE STRUCTURE OF THE PITCHER PLANT.
BY J. G. HUNT, M. D.
“ High among the mountains,
Nepenthe's pitchers weep. ABOUT twenty species of the genus Nepenthes are known to botanists, and while some are natives of swamps in Africa and China, most of the species are found on Mount Kinau Ballou, in the Island of Borneo, growing at an elevation of from three to eight thousand feet above the sea. The species whose minute anatomy we partially describe, is the Nepenthes distillatoria, found growing in China and at the Cape of Good Hope. This plant often attains the length of ten or twelve feet, generally lying prostrate, or partially supported by other plants. It bathes its roots in the hot swamps near the coast, but cannot lift its flowers very high in the sunshine, because its branching stem which bears many long and partly clasping leaves, and also its precious
burthen of watercups, is too feeble to support the weight. Seldom does the stem exceed two inches in diameter, being
long and flexible like a rope.
Now, as all readers of the NATURALIST may not be botanists, we will state that the plants in question bear on the ends of their leaves peculiar appendages not unlike pitchers in form, and hence they are commonly known as pitcher-plants. Like the pitchers we use for domestic purposes, they are often colored with many gorgeous tints, and fashioned into graceful shapes, often with a capacity to hold more than a quart of liquid. As nature is seldom outdone by art, these forest cups have the ability to fill themselves, thus differing in an important respect from the pitchers we use.
For a long time it has been a question where this liquid came from, and our knowledge of the subject is still too limited to say from what part of the plant it is poured out, though it is probable special glands have been set apart to perform that function. To decide this question, certainly, would require close observation on the liv
ing pitchers, and that would be very difficult, “because in their early stages of growth they are tightly closed by the curious lids at the top, and in the young state excretion is most rapid and copious.
Fig. 1 is an accurate drawing made (half size) from a pitcher that had been rendered transparent in order to show
its venation, and the position of both sets of glands. Minute dots, commencing at the bottom and extending to high-water mark,* represent the position and number of one series of Fig. 2.
glands, all on the inside of the pitcher. The under side of the lid also is covered with similar glands, having among them, however, numerous stomata.
Fig. 2 shows a camera lucida drawing (magnified eighty diam
eters) of these glands, also fendered transparent, so that their anatomy may be seen at one view. They are depressed below the inner surface of the pitcher, and have, extending over nearly half the diameter of each, a projection of the epidermis like many little roofs, so that a stream of water poured in at the top would reach the bottom of the pitcher without touching a gland. The fine reticulation marking the surface of each, is caused by the ends of long columnar cells making up the gland structure, and these columnar cells rest on others of larger size, shown in the drawing. All the parts just described are best seen by a perpendicular section (Fig. 3, magnified one hundred and sixty diameters), and it may also be observed that each gland lies immediately over large isolated and spiral cells, which have no vascular connection with the ordinary spiral structure of the plant.
In a description, without illustrations, of this series of glands, published in the "Edinburgh New Philosophical
* Crossing the middle of the pitcher; the dots are omitted in the figure.