190 STUDIES IN LIFE AND SENSE. 



extreme. Draw your finger gently down the middle of his back, and 

 when you touch a given part of Clammyskin's surface, the frog, minus 

 the front lobes, will croak. He will not croak unless you stroke his 

 back : but regularly, as if you touched the " croaking- stop " in the 

 amphibian organ, he will emit his single note, whenever your finger 

 arrives at the stated spot. There is much that is obscure here, but 

 the rationale of the inscrutable croak is at least clear. It is produced 

 by an order of the part of the brain which governs the vocal organs 

 of Clammyskin, and which part is stimulated unerringly and unvary- 

 ingly by the outward stimulus supplied by the touch of the finger. 

 But when possessing his front lobes, the frog may still be made to 

 croak by the application of gentle stimulus to his back, whilst 

 naturally the male frogs are given to croak incessantly at the time of 

 egg-deposition. The male voice asserts itself in a very marked 

 manner over that of the female frogs, and in the scientific version of 



A frog he would a-wooing go, 



the croak counts for much, both as a sign of attractiveness in the 

 wooer, and of his progress in his suit. When we have attained to 

 such heights in the science of mind as may entitle the scientist of the 

 future to write the " Comparative Psychology of the Frog's Wooing," 

 and of the Clammyskin tribe in general, the language of the croak 

 may prove to be more diverse and eloquent than we may now 

 suppose to be possible. There can be no doubt, even in the present 

 state of our knowledge, of the overwhelmingly powerful nature of 

 the oratory prevalent in our ponds and ditches in the months of 

 early spring. 



Vocalisation of the highest types now awaits a brief review ; 

 and perchance, by way of introduction, you may not object to be 

 reminded of the nature of the vocal organs and of that curious 

 machinery wherewith the mind finds outward expression in so 

 many and varied ways. Every one knows that voice comes from a 

 region situated somewhere near " Adam's apple." To be sure, this 

 is no very definite way of expressing the anatomy of the organ of 

 voice, but it serves the purpose of localising the faculty, at any 

 rate. The human " larynx " or voice-organ, to be brief, exists at the 

 top of the windpipe, as a kind of gristly box, composed of elastic 

 and movable cartilages of which " Adam's apple " is both a prominent 

 and important example. This gristly box is placed in the direct 

 track of the air-currents passing to and from the lungs. Its entrance 

 is guarded above by a little lid (the epiglottis] which prevents food- 

 particles from "going the wrong way." Inside the box are two folds 

 of mucous membrane, named the true vocal cords ; other two folds 

 (thefa/se vocal cords) also exist, but the latter do not aid in the pro- 

 duction of voice. By the varying alterations and degrees of tension 



