February, 1908.] 



KNOWLEDGE 



41 



period of courtship but throughout the months of June 

 and July. During this season, espei;ially when the nights 

 are warm and moonlit, the concert begins at sunset and 

 continues till dawu. One of these musical evenings, 

 conducted by a colony of these frogs in North Germany, 

 ■where they are common, his been graphically described by 

 Dr. Gadow. The tuning-up commences, he tells us, with 

 a single note uttered by a few scattered individuals, 

 " qwarr, oo-arr," or " coarx," " qwarr, oo-ar," " coarx." 

 And then the choir-master commences with a shar^) 

 sounding " brekeke." This is the signal for the rest to 

 begin, which they do with a will, bass, tenor, and alto, 

 each performer filling his vocal sacs to bursting size, so 

 that these bags look like a pair of floats, one on each side 

 of the head. When several hundi-eds of these joyous 

 creatures are indulging in this exercise, the din may be 

 heard a mile off. In the Middle Ages it was customary, 

 where these irrepressible creatures abounded, to keep a 

 servant for the sole jmrpose of breaking up the concert by 

 beating the pond, throwing stones, or otherwise disturbing 

 the meeting ! In Foulmire Fen and Whaddon, in Cam- 

 bridgeshire, these frogs, in their palmy days, earned for 

 themselves the names of "Whaddon organs" and "Dutch" 

 or "Cambridgeshire nightingales." 



The voice-pouches of these frogs form, when inflated, 

 as we have already described, a pair of large globular bags, 

 one on either side of the head. They are found only in the 

 males, and are filled through a small opening in the floor 

 of the mouth on each side of the tongue. 



The vocal powers of the American bull-frog, a near ally 

 of the edible-frog, are well known. Assembling in 

 hundreds during the breeding season, the males give voice 

 to a croak so loud as to be compared to the distant roaring 

 of a bull, which can be heard, on a still night, for nearly a 

 mile. 



The blue tree-frog of Australia sends forth, at one time 

 a croaking sound, at another a noise which has been com- 

 pared to the l)arking of an angry dog. Stranger still. Dr. 

 Goeldi, of Para, has recently described a Brazilian tree- 

 frog, known as the " ferreiro " or " smith," which is 

 possessed of a really wonderful voice, making a sound 

 which is compared to the noise made by a mallet slowly 

 and regularly beaten on a copper plate. Regular concerts 

 take place in the forests where these frogs abound, the 

 notes of several individuals varying in tune and intensity. 

 When seized, this extraordinary creature utters a shrill 

 cry which is compared to that of a wounded cat. 



Another tree-frog, this time from North America, has 

 a note which re.sembles a small bell. iSo, too, has one of 

 the 8(iutli American toads, its call-note being described as 

 three bell-like notes, the middle one being the highest. 



Darwin's narrow-mouthed toad is another species with 

 a bell-like note. This species, by the way, is further 

 remarkable in that the vocal sacs, during the breeding 

 season, are used as a depository for tlie eggs! The safety 

 of these treasures is of course of immense importance, but 

 this pafticuhir arrangement for tlieir security must be an 

 exceedingly inconvenient one for tlio father of the family, 

 inasmuch as, until the eggs hatch and the young are 

 extruded, he is rendered perfectly dumb ! 



A remarkable species of frog recently discovered in 

 Paraguay has a cry which has been compared to that of a 

 kitten. The voice is made bv alteraately intlatiug tlie 

 voice-pouches and lungs. When the hitler are fully 

 inflated this frog appears to be as big as a golf-!iall, but if 

 startled the air is immediately expelled, thereby reducing 

 the body to one-filth its former size. 



15eside8 the examples wo have selected for comment, 

 the ranks of the lowly and much-despiseil frogs and 

 toads boast many other performers quite worthy of honour- 



able mention did space pei'iuit. It must not be supposed, 

 however, that it is they ahme who are provided with the 

 curious dilatable sound-boxes ; on the contrary, as we 

 shall now proceed to show, they are to be found in various 

 animals, up to the "lord of creation " himself. 



Amoni; the birds we have two very striking instances 

 in the ostrich and the emeu. The ostrich, like certain 

 other birds which inflate the neck for the purpose o£ 

 display only, transforms his gullet, for the nonce, into a 

 sound-producing organ. This is done by the male only, 

 and when challenging another cock, or courting the 

 female. The sound is described as resemblinK a mufiled 

 " boom," and its production is known by English ostrich 

 farmers as "bromming." It can only be made whilst the 

 bird is standing still, but exactly how it is produced is 

 not quite clear. Possibly the huge column of air in the 

 gullet serves in some way as resonator to the voice organ, 

 whilst, on the other hand, the sound may be produced by 

 the sudden expulsion of the imprisoned air. 



The emeu, far inferior to the ostrich in many things, 

 has decidedly the advantage in matters musical, inasmuch as 

 it has developed a quite unique form of voice organ. This 

 is formed by a long slit pierced through the wall of the 

 front of the windpipe, near its middle, so as to permit the 

 exit of a large pouch formed by tht^ inner lining of the 

 windpipe, so that the pouch comes to lie between the 

 windpipe and the skin of the neck. Although present in 

 both sexes, this pouch, strangely enough, appears to be used 

 only by the female, who, during the time when the cares of 

 a family weigh heaviest, gives voice to a very peculiar 

 booming sound of considerable volume. That the sound 

 is due to the action of the pouch there can be little doubt, 

 for the true organ of voice in the emeu is of a very rudi- 

 mentary character. 



Voice pouches among the higher animals occur but 

 rarely. Traces thereof are to be found, however, in certain 

 whalebone whales and porpoises, some swiae, and the 

 great ant-eater, indicating that at some earlier time these 

 creatures possessed, if not the gift of song, at least the 

 ability to make a noise in the world. 



In the common fox two voice pouches of considerable 

 size are found in the larynx, though not large enough to 

 be visible externally. Probably they are to be found in 

 the wolf, hyaena, and jackal also, and aid not a little in the 

 production of the blood-curdling sounds which these 

 creatures are capable of pouring forth. 



We meet with them again among the members of the 

 monkey tribe, and in man. Among some of the former 

 these pouches are of enormous size, yet, save in one or two 

 cases, they are incapable of producing any sound which 

 to our ears would be called musical ; on the contrary, in 

 many cases they make the night hideous by the most 

 demoniacal of noises. 



The howler monkeys of South America have achieved 

 great distinction in this direction. Waterton, in his 

 " Wanderings," writing of the red howler monkey of 

 Demerara, tells us that " Nothing can sound more dread- 

 ful than its nocturnal bowlings. While lying in your 

 hammock in these gloomy and immeasurable wilds, you 

 hoar him howling at intervals from eleven o'clock at night 

 till day-break. You would suppose that half the wild 

 beasts of the forest were collecting for the work of 

 carnage. Now it is the tremendous roar of the jaguar, as 

 he springs on his prey: now it changes to his terrible and 

 deep-toned growlings, as he is pressed on all sides by 

 superior force ; and now you hear his last dying moan 

 beneath a mortal wound." 



Some naturalists have supposed that these awful sounds, 

 which you would fancy are those of enraged and dying 

 wild beasts, proceed from a number of the red monkeys 



