38 THE VOYAGE OF H.M.S. CHALLENGER. 



long, and in their configuration resembled the petrous bone of Mesoplodon, and, without 

 doubt, belonged to the bullae of this animal already referred to as found in the same 

 station. Others were of the same magnitude as the petrosal in the genus Delphinus, 

 and very similar in form, whilst two specimens were smaller than those of the common 

 porpoise. In all, the manganese had been deposited in the canals and foramina in the 

 bones, and had given a coating more or less thick, in different instances, to the entire 

 bone. Mr Murray has figured three specimens in Plate VIII. figs. 8, 9, 9a, 14 and 14a. 



Fourteen specimens also occurred which consisted not only of the j)etrous, but of a 

 portion of the elongated " mastoid " element continuous with it. These varied consider- 

 ably in size, the largest being 3'6 inches long, and the smallest 2'5 inches, and the latter 

 ■ is figured by Mr Murray in PI. VIII. fig. 3. They were all deeply impregnated with 

 manganese, which had filled up the hollows and foramina, and coated the entire bone, so 

 that it was difficult to obtain an exact idea of its form. It is not unlikely that these 

 may have been the petro-mastoid elements belonging to the tympanic bullae of some of 

 the Baleen whales already stated to have been found in this station. 



In addition to these ear-bones, numerous fragments of other bones were also present, 

 all, with one exception, being deeply impregnated with manganese. The most noticeable 

 of these was an elongated Ijar of bone S'l inches in length, which Professor Flower and 

 I concurred in regarding as the beak of a Ziphioid whale. Sections of the beak were 

 made by Mr Murray which confirmed the accuracy of this opinion. The beak and 

 sections through it are figured by Mr Murray (PI. X. fig. 1, a, h). Three other, but 

 much smaller, fragments of bone, which also seemed to be portions of the beaks of 

 Ziphioids were also present. 



A number of fragments of flat bones, most of which were portions of the brain case, 

 though one or two might have been bits of the shaft of a rib, occurred. The largest, 

 figured by Mr Murray (PL X. fig. 2, a), was marked on its inner surface by a groove 

 for a venous blood sinus. 



An irregular mass of spongy bone, 4 inches by 8, by 3, consisting apparently of 

 a portion of the expanded wing of a superior maxilla, was present. It was noticeable, 

 not only from its size, but from the paucity of manganese deposit as compared with 

 the other bones. Another smaller portion of similar spongy texture was surrounded 

 with nodulated masses of manganese ; this is figured by Mr Murray (PI. X. fig. 3). A 

 third mass, 5 inches by 5, having its surfaces concavo-convex, was covered by, and 

 deeply impregnated with, manganese and iron deposition, so that it had quite a 

 mineral appearance. It was also apparently a part of the expanded wing of the superior 

 maxiUa. Further, there were between one and two hundred smaller fragments, looking 

 on the exterior like nodules of manganese, which, when broken through, exhibited evidence 

 of bone structure. In one the fracture had displayed the helicoidal turn of the cochlea. 



If we were to suppose that the eighty-nine tympanic bullae obtained in this station 



