ANATOMY OF MEGAPTERA LONGIMANA. 



185 



27. HYOID BONE. TABLE III. Measurements of the Hyoid 

 Bone, in inches : 



28. CHARACTERS OF THE HYOID BONE, IN COMPARISON WITH 

 THOSE OF B. MUSCULUS. Although the hyoid bone of B. mus- 

 culus strikes the eye as larger and more massive than that of 

 Megaptera, it would not be so were we to go merely by the 

 comparative length of the two skeletons. But there are differ- 

 ences in form. 1 



Both ends of the stylo-hyals are flat in Megaptera, while in 

 B. musculus the ends differ materially in thickness, as seen in 

 the measurements given in the Table. The anterior conical 

 processes, commonly regarded as outgrowths from the body, but 



1 The hyoid of Megaptera is at once known from that of B. borealis by the 

 broad stylo-hyals of the latter ; also by characters of the body and great horn, 

 especially by the flatness of the great horn in B. borealis. In this 35-feet-long 

 B. borealis the stylo-hyals have not attained the breadth figured by Flower, from 

 the Leyden (Java) finner (Proc. Zool. Soc., 1864, p. 406), and figured, from the 

 same skeleton, by Van Beneden and Gervais (loc. cit., pis. xiv., xv. fig. 28, B. 

 Schlegelii). The vertebrae and other characters figured in that plate leave no 

 doubt that their B. Schlegelii is the same species as my B. borealis. The stylo- 

 hyals in my B. borealis are liker those figured by Van Beneden and Gervais (pis. 

 x., xi. figs. 15, 16, " d'apres le squelette de Leide") in their so-called B.laticeps, 

 except that in mine the lower end is more pointed. In this 35-feet-long B. 

 borealis the greatest breadth of the stylo-hyals is 4 inches ; length 13, the broad 

 part 9, the tapering lower part 5 inches. 



