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EDITORIAL GLEANINGS. 



We have received from Mr. R. M. Dixon, of Bombay, a reprint of 

 his paper on " The Senses of Snakes " (Verhandlungen des V. Inter- 

 national Zoologen-Congresses zu Berlin). We give the following 

 extract : — 



" The organ of hearing in the Snakes is so obscure and defective as 

 to lead one to believe that their sense of hearing was of varying delicacy, 

 if not altogether wanting. Snakes possess not only no external ears 

 for gathering and concentrating the vibrations of sound, but are also 

 destitute of any external orifice by which these may readily enter the 

 auditory organ. They have no tympanum and no traces of the 

 Eustachian tubes. The tympanic cavity also is absent, and in its 

 place there is a long columellar rod, Columella auris, with a special 

 cartilaginous pad at its outer end, which plays against the middle of 

 the shaft of the quadrate bone. This peculiar anatomical structure 

 presumably produces a loud rumbling noise in the internal ear, as the 

 fenestra ovalis is directly affected by the vibrations produced at every 

 motion of the quadrate bones during deglutition. Hence there is 

 reason to believe that Snakes can hear as distinctly as any other 

 animals, though the auditory apparatus in the Ophidic/, is obscure and 

 imperfect. The velocity of sound in the earth is far greater than that 

 in air. Hence the vibrations of a sound mainly transmitted through 

 the earth — as, for instance, the sound of a footfall — may reach a Snake 

 on the ground quicker than one coiled up in the branches of a bush. 

 In the same way the vibrations of a sound mainly transmitted through 

 the air may reach the latter earlier than the former. The undulations 

 may also be transmitted through the medium of water. The velocity 

 of sound in water is four times as great as in air. Thus the vibrations 

 of a sound transmitted through the medium of the earth, water, or air 

 reach the essential organ of hearing whether the Snake is basking in 

 the sun, swimming in the water, or lying coiled up in the branches of 

 a bush. In Psalm lviii. 4, 5, Eccl. x. 11, and Jeremiah viii. 17, 

 allusion is made to that singular phenomenon, the charming of Snakes 

 by musical sounds. The Psalmist compares the wicked to ' the deaf 

 adder that stoppeth her ear ; which hearkeneth not to the voice of 

 Zool. 4th aer. vol. VII., March, 1903. k 



