Page:Encyclopædia Britannica, Ninth Edition, v. 6.djvu/721

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CUC—CUC
687

species becoming hereditary, it will be seen that it requires but an application of the principle of " Natural Selection " to show the probability of this principle operating in the course of time to produce the facts asserted by the anony mous Solognot of the last century, and by Dr Baldamus and others since. The particular gens of Cuckow which inherited and transmitted the habit of depositing in the nest of any particular species of bird eggs having more or less resemblance to the eggs of that species would prosper most in those members of the gens where the likeness was strongest, and the other members would (cceteris paribus) in time be eliminated. As already shewn, it is not to be supposed that all species, or even all individuals of a species, are duped with equal ease. The operation of this kind of natural selection would be most needed in those cases where the species are not easily duped, that is, in those cases which occur the hast frequently. Here it is we find it, for observation shows that eggs of the Cuckow deposited in nests of the Red-Backed Shrike (Lanius collurio), of the Bunting (Emberiza miliaria), and of the Icterine Warbler approximate in their colouring to eggs of those species species in whose nests the Cuckow rarely (in comparison with others) deposits eggs. Of species which are more easily duped, such as the Hedge-Sparrow,

mention has already been made.

More or less nearly allied to our Cuckow are many other forms of the genus from variouj parts of Africa, Asia, and their islands, while one even reaches Australia. How many of these deserve specific recognition will long be a question among ornithologists which need not be discussed here. In some cases the chief difference is said to lie in the diversity of voice a character only to be appreciated by those acquainted with the living birds, and though of course some regard should be paid to this distinction, the possibility of birds using different " dialects " according to the locality they inhabit (see Birds, vol. iii. p. 771, note 1) must make it a slender specific diagnostic. All these forms are believed to have essentially the same habits as oir Cuckow, and, as regards parasiticism, the same is to be said of the large Cuckow of Southern Europe and North Africa (Coccystes glandarius) which victimizes Pies (Pica maurilanica and Cyanopica cooki) and Crows (Corvus comix). True it is that an instance of this species, commonly known as the Great Spotted Cuckow, having built a nest and hatched its young is on record, but the later observations of Dr A. E. Brehtn, Canon Tristram, Stafford Allen, and others tend to cast doubt on the credibility of the ancient report. It is worthy of remark that the eggs of this bird so closely resemble those of one of the Pies in whose nest they have been found, that even expert zoologists have been deceived by them, only to discover the truth when the Cuckow s embryo had been extracted from the supposed Pie s egg. This species of Cuckow, easily distinguishable by its large size, long crest, and the primrose tinge of its throat, has more than once made its appearance as a straggler in the British Isles. Equally parasitic are many other Cuckows, belonging chiefly to genera which have been more or less clearly defined as Cacomantis, Chrysococcyx, Eudynamis, Oxylophus, Phcuni- cophaes, Polyphasia, Surniculus, and Zanclostoma, and inhabiting parts of the Ethiopian, Indian, and Australian Regions;[1] but there are certain aberrant forms of Old -World Cuckows which unquestionably do not .shirk parental responsibilities. Among these especially are the birds placed in or allied to the genera Centropus and Coua the former having a wide distribution from Egypt to New South Wales, living much on the ground and commonly called Lark-heeled Cuckows (an obvious misnomer) tho latter bearing no English name, and limited to the island of Madagascar. These build a nest, not perhaps in a highly- finished style of archifecture, but one that serves its end.

Respecting the Cuckows of America, the evidence, though it has been impugned, is certainly enough to clear them from the calumny which attaches to so many of their brethren of the Old World. There are two species very well known in parts of the United States and some of the West-Indian Islands (Coccyzus americanus and C. crythrophthalmutf), and each of them has occasionally visited Europe. They both build nests remarkably small structures when compared with those of other birds of their size and faithfully incubate their delicate sea-green eggs. In the south-western States of the Union and thence into Central America is found another curious form of Cuckow (Geococcyx] the Chapparal-cock of northern and Paisano of southern settlers. The first of these names it takes from the low brushwood (cliapparal) in which it chiefly dwells, and the second is said to be due to its Pheasant-like (faisan corrupted into paisarto, which is properly a countryman) appearance as it runs on the ground. Indeed, one of the two species of the genus was formerly described as a Phasianus. They both have short wings, and seem never to fly, but run with great rapidity. Returning to arboreal forms, the genera Neomorphits, Diploptertis, Saurothera, and Piaya (the last two commonly called Rain-birds, from the belief that their cry portends rain) may be noticed all of them belonging to the Neotropical Region ; but perhaps the most curious form of American Cuckows is the Ani (Crotophaga), of which three species inhabit the same Region. The best-known species C. ani) is found throughout the Antilles and on the opposite continent. In most of the British colonies it is known as the Black Witch, and is accused of various malpractices it being, in truth, a perfectly harmless if not a beneficial bird. As regards its propagation this aberrant form of Cuckow departs as much in one directi( n from the normal habit of birds as do so many of our familiar friends of the Old World in the other, for several females unite to lay their eggs in one nest. Full details of its economy are wanting, but it is evident that incubation is carried on socially, since an intruder on approaching the rude nest will disturb perhaps half a dozen of its sable proprietors, who, loudly complaining, seek safety either in the leafy branches of the tree that holds it, or in the nearest available covert, with all the speed that their feeble powers of flight permit.

(a. n.)

CUCUMBER (Cucumis), a genus of the natural order

Cucurbitacece, represented by indigenous species in most warm regions of the globe, and distinguished by the following characters : plants, annual or possessing a perennial thick root ; stems, rarely if ever climbing ; leaves heart-shaped, sometimes reniform, with three to Sfeven lobes, and crenulate or denticulate margin ; flowers, monoecious and yellow, having tubular campanulate. calices, petals but slightly adherent, three free stamens, and a tripartite, obtuse, and spheroidal stigma ; fruits or pepones, three to six celled, smooth or echinate ; and seeds, more or less compressed, ovate, sharp-edged, and of a yellow or dirty-white colour. Ciicumis sativiis, the common cucumber, is an annual, indigenous probably to tropical Asia; the branches ramify little ; the leaves are hairy and have three to five sharply-pointed lobes ; the ovary is often fusiform ; the fruits are for the most part oblong, obscurely trigonal or cylindrical, and except in one variety contain three carpels, and their flesh is white, firm, and of an agreeable sub-acid taste. In its characters it is one

of the most uniform species of its genus. The principal





  1. Evidence tends to show that the same is to he said of the curious Channel-bill (Scythrops nows-hollandm), but absolute proof seems to be wanting.