418 



Mr. H. J. Watt. 



Table IV. 



No. 



.Animal. 



Index of 

 basilar 

 membrane. 



No. of 

 whorls. 



Absolute 

 length of 



basilar 

 membrane. 



Ranking 



of 

 basilar 

 membrane. 











mm. 





20 



Common Weasel 



8 -16 



3i 



20 -4 



10 



18 



Mongoose 



7-86 



3 



27 -5 



17 



39 





7 -34 



4* 



51 -4 



37 



37 



Hairy-footed Jerboa 



7-08 



24 



17 -7 



7 



47 



Vulpine Phalanger 



6 -92 



H 



27 -7 



18 



12 



Tiger 



G "55 



Si 



52 -4 



40 



2 



Yellow-faced Baboon 



6-47 





38 -8 



31 



29 



Common Pig 



6 -40 



3£ 



35 -2 



25 



5 





6-37 



2f 



36 -6 



27 



19 



Otter 



6 35 



3 



25 -4 



13 



17 



Aard Wolf 



6 -34 



34 



44 -4 



35 



16 



Dog 



6-16 



34 



38 -5 



30 



3 



Blank Ape 



6-12 



n 



36 -7 



28 



31 



Three-toed Sloth 



5 -93 



2i 



32 -6 



24 



13 





5 -82 



34 



52 -4 



27 



35 



Common Rat 



5 -80 



24 



14 -5 



4 



7 



Common Marmoset 



5 -69 



22 



25 -6 



14 



4 





5-66 



2f 



29 -7 



20 



38 



Common Squirrel 



5-60 



2* 



18 -2 



8 



9 



Slow Loris 



5-52 



24 



20 -7 



11 



25 





5-47 



24 



41 -0 



32 



51 



Brush-tailed Phascologale 



5 -43 



24 



16 -3 



5 



52 



Short-nosed Bandicoot 



5 -43 



. 24 



16 -3 



5 



45 



Brush-tailed Wallaby 



5-38 



3 



24 -2 



12 



10 



Indian Fruit Bat 



5 -34 



2 



18-7 



9 



22 



Common Seal 



5 -31 



24 



53 1 



41 



8 



Mongoose Lemur 



5-28 



24 



26 '4 



16 



49 



Pouched Jerboa Mouse 



5-25 



If 



10 -5 



2 



21 





5 -25 



24 



31 -5 



23 



26 



Indian Gazelle 



5-24 



24 



36-7 



28 



46 





5-22 



2i 



31 -3 



22 



30 





5 -18 



24 



46 -6 



36 



23 



G-rey Seal 



5-18 



2 



51 -8 



39 



42 



Whale 



5 -11 



2 



104-7 



42 



1 



Man 



5 -10 



2f 



42 -1 



34 



28 





4 '90 



2£ 



51 -4 



37 



32 



Tamanduan Anteater 



4-89 



2 



25 -7 



15 



41 





4-65 



If 



9 3 



1 



24 





4-65 



24 



27 -9 



19 



27 





4-26 



24 



29 -8 



21 



43 





4-21 



If 



35 -8 



26 



40 





3-97 



1* 



11 -9 



3 



44 



1 





3-95 



14 



41 -5 



33 



This ranking can hardly be taken strictly as it stands, but it will be 

 valid on broader lines. Half the number of organs measured have an index 

 of five and a fraction. An index of over 6 - 5 may safely be held to be 

 unusually large, an index of below 4 - 5 unusually small. I should divide 

 the whole group into two parts at the index of 5 - 5 ; that gives two rather 

 characteristic groups, in the first of which are many carnivora and some 



