586 



ANATOMY OF VERTEBRATES. 



459 



Larynx of Hedgehog. 

 cccxx. 



CCXVin", p 34. At the apex of the arytenoids are the con- 

 fluent ( cartilages of Saniorini,' ib. />. The cricoid, c, has a median 

 longitudinal ridge behind. The vocal cords are short, and at- 

 tached interiorly to the lobes of the base of the epiglottis, the 



lower chord is the strongest ; the ' ventricle ' is 

 produced into a sac between the epiglottis and 

 hyoid. The Hedgehog's squeak is seldom heard. 

 The larynx of Shrews and Bats agrees in the 

 main with that of the Hedgehog. In a large 

 frugivorous bat (Pteropus) 1 the wings of the 

 thyroid coalesce anteriorly for a short extent : 

 the cricoid, fig. 460, c, has the posterior longi- 

 tudinal ridge : the epiglottis is broad with an 

 acute apex : besides the arytenoids and their 

 apically confluent ( Santorinian cartilages,' d, 

 there are the l sesamoid cartilages,' b, and an ' intercellular carti- 

 lage,' f, narrower than in the hedgehog, and of an oblong form. 

 The inferior vocal cord is sharply produced, but is short and 

 narrow : the ventricle is not dilated into a sac. 



In the Sloths the upper vocal cord is obsolete ; the lower one is 

 well defined but short ; the ventricle is shallow. The voice of 



the Ai (JBradypus tridactylus} is feeble and 

 plaintive ; that of the Choloepus didactylus^ cap- 

 tive at the London Zoological Gardens, has 

 never been heard there. The Armadillos, also, 

 appear to be habitually mute : only the lower 

 vocal cord is manifest : the ventricle is obsolete : 

 the epiglottis is deeply notched at the apex. 2 In 

 the great Anteater {Myrmecopliaga jubata) the 

 thyroid cartilage is ossified. The cricoid is car- 

 tilaginous. The arytenoids are low obtuse carti- 

 lages. The lower ' chordae vocales ' extend from 



o 



the arytenoids forward, the fold containing them 

 expanding as they advance. There is a shallow fossa beneath 

 this fold and a deeper one representing the ventricle above it. 

 A small ' iriterarticular ' fibro-cartilage supports an obtuse pro- 

 minence near the hinder ends of the epiglottidean folds, which 

 are continued back to the arytenoids. 



The larynx includes, in Cetacea, the usual Mammalian carti- 

 lages, much modified in shape and proportions. The thyroid in 



1 Referred by Brandt to Fteropus Vampirus, in ccxvm"; and by Bishop, who 

 copies the figure, to Plu/llostoma Spectrum, cccxx, fig. 898. 

 * cxxvii". p. 144. 



460 



Larynx of Pteropus. 

 cccxx. 



