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REPRODUCTION AND SEX 471 



case, one partner forms the main body of the plant, while the other 

 partner forms the skin only, or the epidermis plus the hypodermis. 

 This strange mosaic is a type of chimaera, and recent investigation 

 has shown that Adam's Laburnum, whose secret we have been 

 deferring, is another dual plant or chimsera, the main body being 

 that of a Yellow Laburnum, while the skin is that of the purple 

 species. 



Homer's chimaera had the head of a lion, the body of a goat, and 

 the tail of a dragon; and others depicted in ancient literature and 

 heraldry were similarly impossible combinations. The zoologist's 

 Chimaera (e.g. C. monstrosa), is a remarkable fish, sometimes caught 

 off British coasts, which the fishermen curiously call the "shimmer"; 

 and it probably owes its technical name to the impression that it 

 is a sort of impossible combination of characters. 



But there are in the Animal Kingdom a few genuine chimaeras 

 in the technical sense — mosaics that man has made. Unfortunately, 

 as regards impressiveness, they are mostly confined to early youth, 

 and they are all very small when compared with Adam's Laburnum. 



It is not very difficult to graft a piece of one animal on to another 

 of a related species. Serious wounds have sometimes been mended 

 in this way, and everyone knows of the transfusion of blood. There 

 is nothing chimerical about this. 



On the other hand, it is possible to graft together the very 

 early stages of two different species of newt (e.g. Triton cristatus 

 and T. tcBuiatus), with the result that they combine harmoniously 

 and go on developing, each keeping to its own species! And just 

 as in the plant world, so among these amphibians, the chimaeras 

 are of two kinds. A region of the young animal, perhaps a whole 

 side, may be of the one species; while another region, or, it may be, 

 side, is just as clearly of the other species. This is called a "sectorial" 

 chimaera. In other cases, reminding one of the Pelargoniums, the 

 skin belongs to the scion and the rest of the body to the stock. This 

 is called a "periclinal" chimaera. In both types of amphibian chimaera 

 there is a combination, but not a mingling, of the two components. 

 Another chimaera has been made by artificially combining the stalked 

 freshwater polyp, Pelmatohydra, and the ordinary unstalked 

 Hydra. They combine intimately and get on well together, but they 

 do not in any sense mix. It sounds rather chimerical, but there it is. 



CONSANGUINITY. — When we speak of a consanguineous union, 

 we mean that the two organisms are near relatives ; when we speak 

 of a high degree of consanguinity in a herd or in a community, we 

 mean that there has been much in-breeding or endogamy. In regard to 

 the results of this sex-union of closely consanguineous organisms, it 

 must be admitted that clear-cut facts are few. It should also be 

 noted that, as the range of Hving creatures expresses a very long 



