42 



KNOWLEDGE 



[February, 1903. 



howling in concert. One of them alone is capable of 

 producing all these sounds. 



The howler monkeys appear to have gone to considerable 

 trouble and pains to produce these c!xtraordinary sounds, 

 for even the bones of the skeleton have been altered in 

 consequence. The resonating voice pouch of these monkeys 

 is formed by an outgrowth of tlie membrane lining the 

 windpipe; to be more exact, of the inner lining of the 

 larynx, the region of the windpipe wbich forms the 

 " Adam's apple " in man. It is of enormous size, and to 

 afford it support the bones of the tongue have been induced 

 to form a huge cup-shaped chamber, and to protect this, 

 the lower jaw has further developed abnormally deep sides, 

 so that the long chamber with its thin-walled pouch is 

 most effectually protected. 



The man-like apes — the gibbons, gorilla, chimpanzee 

 and orang-utan — are all provided with these peculiar 

 pouches, and all have remarkably powerful voices. 



The pouches of the gibbons are relatively small — in one 

 species, the Siamang gibbon {Rylohates nyndadylus) of 

 Sumatra, they are said to be wanting — but at least two 

 species are capable of producing musical sounds. Thus, 

 the notes of the agile gibbon have been described as 

 ascending and descending the scale, the intervals being 

 exactly half tones. The highest note an exact octave 

 higher than the lowest. The silvery gibbon, Mr. Francis 

 Darwin tells us, sings in a cadence of three notes in true 

 musical intervals, with a clear musical note. The wan- 

 wan gibbon {Hylohates leuciscus) is a decidedly less 

 pleasing songster. Dr. H. O. Forbes, in describing this 

 species, which he met with in Java, tells us that in the 

 evening, just about sundown, and again, just before sunrise, 

 the traveller is often startled by the sudden outbreak of what 

 appears to be, now the loud plaintive wailings of a crowd 

 of women, now the united howlings of a band of castigated 

 children. Eventually the harrowed feelings of the listener 

 are relieved by the discovery that these woeful cries are 

 merely the outbursts of a band of monkeys serenading 

 their neighbours. 



The gorilla, chimpanzee, and orang surpass even the 

 howler monkey in their ability to make a noise. 



The gorilla is described as being able to emit "a terrible 

 yell that resounds far and wide through the forest." The 

 orang in producing high UDtes thrusts out his lips into a 

 funnel-shape ; but in uttering low notes the mouth is 

 held wide open. The chimpanzee, like the howlers, give 

 vent to loud cries, shrieks, and howls in the morniu" and 

 evening and sometimes during the night, making a noise 

 which can be heard for great distances. 



So far, however, we appear to have more information 

 concerning the size and structure of the voice pouches of 

 the large apes than of the noises which they produce. 

 These pouches are formed by outgrowths of a pair of 

 cavities of the larynx or organ of voice known as the ven- 

 tricles of the larynx. In the gorilla and the orang they 

 are of enormous size. In the former they cxteud from 

 the throat downwards over the breast to the armpits ; 

 whilst in the latter they encircle the neck, so as to give 

 the creature the appearance of wearing a life-buoy beneath 

 the skin. In the chimpanzee these sacs appear to be 

 somewhat less developed, and are three in number, a 

 median and two lateral. 



In man himself it is interesting to notice vestiges of 

 tbe.se pouches are found within the larynx, behind the 

 " Adam's apple." It is, perhaps, fortunate that they have 

 sunk into desuetude, for one trembles to think of the 

 numerous street cries, brawls, and the efforts of pe"-!- 

 patetic orators that even now hairow our feelings, mag- 

 nified ten-fold by resonators of this description ! 



A GIANT AMONG SEALS. 



By R. Lttdekker. 



Few generalisations have taken a firmer hold of the 

 popular imagination than the notion that the animals of 

 to-day bear no sort of comparison with their jiredecessors 

 of the past in respect of bodily size, and that, so far as the 

 giants of the animal kingdom are concerned, we are living 

 in a dvjarfed and impoverished world. Like most popular 

 conceptions this idea contains a considerable element of 

 truth mingled with a large amount of misconception. In 

 the first place, there is no accurate definition of what is 

 meant by " the past." If it mean only those epochs of 

 the earth's history previous to the advent of man, it is 

 unquestionably inaccurate. If, on the other hand, it also 

 embrace the prehistoric portion of man's sojourn on the 

 globe, it has scarcely a claim to be regarded as a fair or 

 accurate statement of the true state of the case, seeing 

 that the extermination of a very considerable percentage 

 of the large animals of the epoch in question has been the 

 work of man himself — a work, unliappily, which is still 

 proceeding apace. 



But in addition to this, the animals of one geological 

 epoch are very fi-equently confounded with those of 

 another, so that dinosaurs and mosasaurs, ichthyosaurs 

 and plesiosaurs, mastodons and mammoths, and glypto- 

 dons and ground-sloths, are ofteu spoken of as if con- 

 temporaries and inhabitants of the same country. 



If such were really the case, we should indeed be living 

 in an impoverished epoch of the world's history ; but if 

 we take the term "present" in not too narrow a sense, 

 and also bear in mind that Europe, and such other parts 

 of the world as have been more or less thickly populated 

 for untold ages, scarcely form a fair basis of comparison, 

 it will be manifest that the idea in question is to a con- 

 siderable extent due to misconceptions and inaccuracies of 

 the nature of those referred to above. 



It is true that in certain portions of the world the larger 

 forms of animal life disappeared at an epoch when man 

 can scarcely be regarded as having taken a prominent 

 part in their extermination ; a notable example of this 

 kind being South America, where the huge ground-sloths, 

 toxodons, and macrauchenias of the latter part of the 

 Tertiary epoch disappeared with seeming suddenness in 

 what is to us an unaccouutable manner. The extermina- 

 tion of the mammoth, the woolly rhinoceros, and the 

 hippopotamus from Europe, although partly, perhaps, 

 attributable to climatic change, has not improbably been 

 accelerated by man's influence, and the same may be true 

 with regard to some of the larger mammals of ancient 

 India. 



In the latter country we have, however, still the Indian 

 elejjhant, the great one-horned rhinoceros, and the wild 

 buffalo, which, although not actually the largest repre- 

 sentatives of their kind, are still enormous animals. In 

 Africa the prevalence of animals of large corporeal bulk 

 is more noticeable. Although the extinct elephant of the 

 Norfolk " forest-bed " is stated to have been the biggest 

 of its tribe, it is very doubtful if it was really larger 

 than the living African elephant ; and the so-called white 

 rhinoceros, in the days of its abundance, was certainly not 

 inferior in point of size to any of its extinct relatives. 

 The giraffe, again, which in the Mount Elgon district is 

 stated to tower to twenty feet, is much taller than any extinct 

 (juadruped yet known to us ; and the hippopotamus falls 

 but little short of its ancestors of the Pleistocene epoch. 

 The elands, again, are by far the largest of antelopes 

 known at any period of the earth's history ; and the 

 ostrich, although not comparable with some of the New 

 Zealand moas (which, by the way, were probably exter- 



