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-Bath.

atism, in the stiff. ong continued inus cutaneous disly. While in the formed me, that, aths' duration, he persons into the ing the discipline as I saw him (he to the bath), and hould entirely re

inclined to consie remedy in some similar establish

ons.

ERICK FABER.*

Is of M. Boie in e complete devewith the external but I doubt very feathers off their es of Colymbus, heir belly during however, at this r abdomen than artly by the fric al warmth which

he Iceland grous, and belly nearly t of the feathers the next period. ong some of the ck off a number

1 on the

M. Faber on the Breeding Spots of Birds.

21

of feathers from one or more spots of the belly on the development of the pairing impulse, and before they have laid any eggs, or have begun to hatch. This gives rise to certain naked spots, which I call Breeding spots. The utility of this arrangement is various. There is generally so thick a layer of feathers upon the belly of most aquatic birds, that without some process of this kind, the eggs would hardly ever be brought directly in contact with the skin of the mother. In the second place, most aquatic birds have no nest, or other means of furnishing warmth to their eggs, even in the coldest climates. The breeding spots thus form as it were a nest on the body of the parents, as they collect with their bills all the eggs into this artificial cavity, so that they are quite surrounded by the feathers.

The discovery of this peculiar phenomenon in the history of the boreal birds is entirely my own. Only occasionally do we find former writers directing our attention to these breeding spots, but none seem to have recognised their real importance. Being only found in the boreal birds, the discovery was reserved for a naturalist who had an opportunity of spending the summer in their native haunts. Gunnerus remarks of the Procellaria glacialis*, that he had found no such cavity, but that the medical student Martin had observed them to possess a hole under the crop beneath the large feathers, which he thought might perhaps serve for the hatching of eggs. Fabricius remarks, also of this bird, that he had found this hollow; his words are, Aream deplumem sub abdomine etiam reperi. M. Boie has observed, in his Travels (p. 192), which were written at the same time with my Prodromus, with respect to the Lestris parasitica, that this bird lays only two eggs, and shews that the two parents, which sit alternately, have on both sides of the belly a naked spot, of the size of one of the eggs, and the editor hazards the conjecture that these naked spots may be found in many others of the aquatic and wading tribes,

The true uses of these spots I shall now endeavour to unfoldBirds seldom pluck off their feathers in order to lay them in the Those which are most naked of all during the breeding season, either build no nest, or have no feathers in it. Only

nest.

*Mem. of the Drontheim Soc. i. 198.

[graphic]

M. Faber on the Breeding Spots of Birds.

the Anas and Sula tear out their feathers to line th Therefore, we do not find in the nest the feathers wh been taken off the body of the bird. It is necessary th tion of the great mass which covers the abdomen be re order that the eggs come into immediate contact with dermis. This is the first use of the breeding spots. however, be their only use, because they are wanting of the aquatic birds of the compound monogamy, whos feathers, as just mentioned, is no thinner, as in the Carbo. They must, therefore, be intended to envelope nish the eggs with warmth.

I have found these breeding spots only in the boreal birds, and confined to those species which belong to th or compound monogamy. It would be extremely inte their existence could be established in the aquatic birds zones*. They are never found in the genera Colymbus diceps, which belong to the partial monogamy. They ar wanting in those simply monogamous, as the Mergu Anser, Cygnus. But all these birds have the habit of out their feathers for the purpose of lining their nest does not exist in those birds which belong to the perfe gamy, such as the Phalaropus, Uria, Alca, Mormon Puffinus, Sula, Sterna, Larus, Lestris, and Procellaria. ing spots are found in all these genera, with the exceptio Sula and Carbo.A olled rida Bastol

As both male and female of these species share the la hatching, the breeding-spots are found in both sexes, remarkable exception, however, of the Phalaropus, wh exist only in the male +. Among the many hundred ind

Since the above was written, I have had an opportunity of asc the existence of these breeding-spots in the Danish gulls and seaduring a zoological excursion in the summer of 1824. They exist the male and female of the Larus argentatus, L. ridibundus, Sterna an pia, nigra, and minuta. Their position and number is the same northern individuals of these species. In some wading birds, of bo as the Charadrius hiaticula and albifrons, I found a spot in the midd abdomen, besides a thinner cover of feathers on the breast, which t in common with most land birds, and the other wading birds, at the the other wading birds, at the

+M Holbel has since assured me that in Greenland, he has

Birds.

line their nests. hers which have ssary that a porn be removed, in ct with the epipots. It cannot, Fanting in many y, whose coat of n the Sula and envelope and fur

e boreal aquatic
ng to the perfect
nely interesting if
tic birds of other
Colymbus and Po
They are equally
- Mergus, Anas,
habit of plucking
heir nests, which
the perfect mono-
Mormon, Carbo,
ocellaria. Breed-
e exception of the
are the labours of
h sexes, with the
opus, where they
ndred individuals

unity of ascertaining
lls and sea-swallows,
They exist both in
is, Sterna arctica, cas-
the same as in the

birds, of both sexes, in the middle of the ast, which they have irds, at the breeding

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M. Faber on the Breeding Spots of Birds.

23

of these species which I have examined at the breeding season, I have not seen a single instance of these being wanting, or of their varying in position and number in the individuals of the same species. For they are not a consequence of an unusual deficiency of feathers in these birds, but they follow the most precise rules both in regard to position and number, and furnish a sure specific character of the different boreal aquatic birds.

Their number is only two; in my prodromus (p. 90.) it is indeed stated that the Larus tridactylus has from three to four. But I had before me at the time specimens which were only commencing the process of the removal of feathers from the belly; and I do not doubt, but that, as in the other northern gulls, these different patches would have united into a single one in the centre of the abdomen, when it had assumed its finished form. The Phalaropus, Uria grylle and alle, Alca torda, Mormon fratercula, Lestris, have two breeding spots. The Uria brunnichii and troile, Puffinus arcticus, Sterna arctica, Larus tridactylus, glaucus, marinus, and the Procellaria glacialis, have but one spot. One of the most important distinctions between the Alca torda and Uria troile auctorum is, that the former has two and the latter but one breeding spot.

In regard to position, they are always on the belly, never on the breast; and when one only is present, it is constantly in the middle of the belly; when two exist, they are symmetrically on each side. Their form is circular and proportioned to the size and number of the eggs which they have to cover. A central spot is always larger than each of a pair.

Their number occasionally corresponds to that of the eggs, but sometimes there are more eggs than spots, as in the Larus; in the Alca torda, and Mormon fratercula, the spots exceed the eggs in number. When a bird has more eggs than spots, these are generally large, and capable of including more than a single egg. When the spots are more numerous than the change their position.

eggs,

these

from the deficiency of the breeding-spots in the Phalaropus, a similar defect in the breeding impulse? This genus would then be a solitary exception, of one individual laying the eggs, and another hatching them. It must, however, be observed in general, that we can always infer the breeding impulse to be present when breeding-spots exist, but not vice versa; as, for example,

neither sex of the Sula or Carbo has breeding spots although both batch

[graphic]

M. Faber on the Breeding Spots of Birds. The Uria grylle, Lestris catarractes, pomarina, an tica, have two eggs and two breeding spots. The U nichii and troile, Puffinus arcticus, and Procellaria have one egg and one spot. The Uria alle, Alca t Mormon fratercula, have but one egg and two breedi

The Phalaropus cinereus, and Platyrhinchus, lay 1 and have but two breeding spots. The Sterna arcti glaucus, marinus, and tridactylus, have sometimes th times two eggs, but constantly only one breeding spot.

These spots are not entirely meant to supply the p nest; they are, therefore, not invariably in an inverse the building impulse. Certainly, the species which w spots, as the Sula and Carbo, build a nest; most of th which are provided with them build no nest, as the Ph Uria, Alca, Morindu, Puffinus, Sterna, Lestris, Pro but the genus Larus have breeding spots and build ne

Their presence is therefore merely a proof of the dev of the pairing impulse, but is not to be considered as mous with the laying of eggs or hatching. Birds pluck feathers before even they have joined their mates, and being certain of breeding that year. Therefore I hav them in May, in individuals of the Lestris catarractes, a cellaria glacialis, which were so far out at sea, and from the breeding places of the species, that I had goo for reckoning these barren birds, which pass the summ out breeding. They also exist in the single individual Lestris parasitica, which flock about together.d

After hatching is over, these bare spots are very again covered with feathers. All traces of them hav peared in August and September, when the young species are not yet fledged.

Analysis of the Stony Pericarp of the Lithospermum of By Captain CHARLES LE HUNTE. (Communicated Author.)

be considered one of the most remarkable sub

Birds.

ina, and parasi The Uria Brun-ellaria glacialis, Alca tordu, and breeding spots. s, lay four eggs,

a arctica, Larus

mes three, someng spot. y the place of a inverse ratio to which want these ost of those, also, the Phalaropus, ris, Procellaria; build nests. the development ered as synony Is pluck out these tes, and without re I have found ractes, and Proea, and removed had good cause he summer withndividuals of the

re very quickly nem have disapof some young

Analysis of the Pericarp of the Lithospermum officinale. 25 seeds resemble small, pear-shaped, porcelain beads; they are very hard, difficult to break, and have a high polish. When heated, they at first become black; but they do not shrink, nor does a white heat change their form, in the slightest degree; it destroys, however, their lustre, and renders them, when the vegetable matter has been consumed, whiter than they were originally. Before the blowpipe, small pointed fragments of the pericarp may be partially fused; but this requires a good heat. To determine the nature and quantity of the earthy constituents, the pericarps were carefully separated from the enclosed seeds, and exposed to the action of dilute muriatic acid; a violent effervescence immediately commenced, which did not entirely cease for upwards of two hours. At the end of twelve hours, the acid liquor was decanted, and the pericarps were well washed. Their appearance was not in the least changed; when dried, at a moderate heat, they still retained their original lustre. The acid liquor was found to contain a great deal of lime, a very little phosphate of lime and oxide of iron, with traces of potash and magnesia, which were separated in the usual manner.

The pericarps were then heated to destroy the vegetable matter, which it is exceedingly difficult to effect; but, notwithstanding the intense heat employed, the form of the fragments was not changed by it, they merely lost their lustre, and became very white. When the vegetable matter was entirely consumed, they were again treated with muriatic acid, and left in a warm place for several hours. The acid took up a very little phosphate of lime and oxide of iron. The matter insoluble in the acid, was fused with carbonate of soda, and found to be pure silica. The analysis was repeated, and the composition of the substance appeared to be very uniform. The following is the result:

rmum officinale. municated by the

kable substances nical and chemi

Carbonate of Lime,

Silica,

Vegetable matter, small quantity of phosphate of lime and
oxide of iron, with traces of potash and magnesia,

43.70

16.5

39.8

100

The silica appears to form the polished surface of the seeds. As the acid acted upon the vegetable matter of the pericarps,

and took un

little phosphate of lime and oxide of iron that

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