CHAPTER XVII.

INTELLIGIBILITY OF EACH OTHER'S LANGUAGE.

THE different individuals of the same species thoroughly understand the language of the species, whatever be its nature. It is as intelligible to the whole community as is the language of any nation of men to the individuals composing the nation; much more so indeed, when it is remembered that among civilised peoples at least, what is called and considered the proper language—as written, printed, and spoken-of the people, is intelligible only to the educated; while the special language of one class is unintelligible to those who are not members of the class, or who have not studied its special phraseology.

Animals then of the same species have mutual understandings. They show in a thousand ways how speedily and readily they interchange feelings and ideas; receive and communicate information; realise each other's position, wants, or wishes. They make instant response or reply to the calls or signals of their fellows, whether in the wild or domesticated state, and domesticated to those of wild animals, or vice versa-as in the goose, ape, or elephant. The number and variety of the feelings and ideas which are communicated to each other by the ant and hive bee are pointed out by Houzeau. The leader of wild horse or elephant troops makes his wishes or orders on the march or in defence thoroughly known to the rest (Watson).

Gestures of mutual understanding between the sexes take place in the fowl (Darwin). The mother fox's plaint or wail is understood and obeyed as a danger signal by her young (Houzeau).

INTELLIGIBILITY OF EACH OTHER'S LANGUAGE.

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The dog conveys his wishes and purposes to his fellows (Low), but how he does so does not always appear-for instance, among the pariah dogs of Damascus, according to Mrs. Burton. The dog issues invitations to his companions -to share food, to go poaching, to assist in defence or punishment, and the others accept or decline these invitations (Cobbe).

Certain animals use different danger signals for different kinds or degrees of danger, and their relative significance is thoroughly understood by those for whom they are intended. Certain other animals engage in their assemblies in discussion or debate, which is understood by the whole body of auditors or spectators. The alarm notes of the sentinels of many gregarious animals are instantly understood. In ants on the march there is communication of intelligence throughout the troop. They show their mutual understanding in asking aid, issuing invitations, and giving advice (Figuier).

Bees give each other information of their projects. Their sentinel or watchman issues his summons to defence, which command is instantly understood and obeyed. They beat to arms' (figuratively) when defence becomes necessary in threatened danger (Figuier). Their power of communication with each other before they swarm is commented on by Watson. The warning cry of cattle in danger collects the whole herd, to act on the defensive or offensive (Pierquin). The despatch and reception of news is described in rooks by Watson. The issuing and accepting of invitations is illustrated by bower-birds inviting their neighbours to their dancing assemblies.

Sound becomes an important means of establishing identity-of recognising each other-when there is a change both of aspect and smell. For instance, the bleat of the sheep or lamb, after sheep-shearing or washing, leads to mutual recognition by mother and offspring (White). Response of the young to the old-to the parental call-notes of birds, for instance-implies an understanding on both sides of the significance of the sounds (Houzeau).

According to Belt, foraging ants follow each other by scent, and communicate intelligence-for example, as to the

presence of danger or booty-by the different intensity or qualities of the odours given off.’

In some cases a species-or certain individuals thereof— learn the language, or to understand the language, of other species, genera, or groups.

The rapidity of the acquisition of the language of other species varies greatly, as does also necessarily facility of acquisition. Thus of a hen that, as foster mother, brought up, or tried to bring up, three orphaned ferrets, Romanes says: It took the hen one day to learn the meaning of their cries of distress.' But he could not say that the young ferrets ever seemed to learn the meaning of the hen's clucking.'

The acquisition of the language of other species is not confined to, though it is best illustrated by, the imitation of voice-sounds. It includes the whole phenomena of mimicry -of

1. Man's voice, speech, tone, talk, whistle, words.
2. The songs of a considerable number of birds.

3. The calls or cries of various animals, made use of for the purposes of decoy or deception.

The mocking-bird successfully imitates the hen's call, and the cat's mew (Houzeau). The starling mimics man's voice, the cries of certain quadrupeds, and the song of various birds. The spotted hyæna counterfeits the bleat of the lamb.

Acquired songs consist frequently of combinations of the notes of different species, forming a medley therefrom. However, in acquiring the notes or songs of other birds, it occasionally happens that a species or individual loses its own-for instance, the redbreast (Houzeau).

From intimacy of association with them, the dog soon comes to understand the language of several different genera and species of other animals. For instance, it learns the signification of various bird-calls, including those of poultry, and takes advantage of this knowledge; its action or behaviour is in accordance with the nature and significance of each cry or call (Houzeau).

The language of blandishment or command of the collie