7. SIBBALDIUS. 185 



processes arc smaller and more tapering, than in FJu/salus ; but 

 otherwise its general form is not dissimilar. Its extreme width in 

 a straight line is 25" ; its antero-posterior length 10|". The stylo- 

 hyals (fig. 48) present a remarkable modification in form. Instead 

 of the usual subcylindrical shape seen in Phi/salus and Balcenoptera, 

 they are very broad and flat, and much curved, having a convex 

 rounded border and a concave thin edge, their flat surface having 

 somewhat the form of a crescent with truncated ends, 15" long by 

 6" broad. Their greatest thickness at the convex border is about 

 1|". The ends are not alike, one being narrower and thicker, the 

 other broader and flatter. The two bones are precisely similar. 



" In the present case I have carefully compared the skeletons 

 (that from Java and those from the European coast) together. I 

 have even had the advantage of jjlacing many of the bones of the two 

 in the Lcyden Museum side by side ; and I confess that, allowing 

 for difference of age, it is difficult to fix upon any characters in 

 which they decidedly diff'er. The stylo-hyoids in the first, it may 

 be said, are broader than in the Berlin or Brussels specimens, the 

 sternum larger and of more definite cross-hke form than in the 

 Leyden skeleton, the transverse processes of the vertebrae are more 

 developed and united at their ends than in either of these ; but such 

 characters are of no value for specific distinction. One, however, 

 does appear to me of some importance, and that is the form of the 

 orbital plate of the frontal, so decidedly narrower at the outer end 

 in the Javan crauiimi than in the three specimens from Europe ; 

 but it is possible that even here age may cause the diff"erence. 

 Eschricht has laid great stress upon the little de2)endence that can 

 be placed upon the proportions of the bones of the head in making 

 out the specific characters of WTiales. It is rather curious that the 

 tympanic bones, though agreeing in general form, are actually smaller 

 in the Java than in the Zuyder Zee skeleton, being less in length by 

 0"-3, and in breadth by nearly the same amount. 



" Moreover, although a comparison of osteological details of the 

 immature bones of the other specimens with those of the adult Ostend 

 example was not Hkely to thi'ow much light upon the subject, here 

 the case is diff'erent ; as far as can be made out from the descriptions 

 and drawings given by Dubar of the Ostend skeleton, there are 

 notable diff'erences, as in the form of the atlas, of the first rib, of the 

 stylo-hyoid, in the statement that the second and three following ribs 

 have heads reaching the bodies of the vertebrae, and in the statement 

 that the transverse processes of the third, fourth, and fifth cer^^cal 

 vertcbrte do not unite to form a comi)lete hole as in the second, 

 which last, however, would be of greater importance if the figure 

 did not throw some doubt upon its accuracy. 



" A skull of a very young whale, in the Leyden Museum, is of great 

 interest as having been brought from Java by the late Dr. Rein- 

 hardt. It is labelled ' Balcnoptera Joiu/imana,' and has in conse- 

 quence been (]Uoted in some of our most esteemed catalogues as 

 CN'idencc of the extensive geographical range of that species (Van 

 Beneden, ' Faunc Littorale de Bclgique,' p. 38, and after him. Gray, 



