REPORT ON THE CETACEA. 39 



had been exact pairs, and that the numerous petrous bones all belonged to the same 

 animals as the tympanic buUas, it would follow that the remains of at least forty-five 

 whales were brought from the bottom of the ocean in this single station by one haul of 

 the dredge ; but as the bones were not in pau's, the remains of a much larger number of 

 whales were obtained in this station. It may further be noted that a recognisable pro- 

 portion of these animals were Ziphioids, and many of them belonged to the genus 

 Mesojylodon, so that the central part of the South Pacific Ocean is obviously a favourite 

 habitat of this family of cetaceans. 



Station 131, lat. 29° 35' S., long. 28° 9' W., October 6, 1873, 2275 fiithoms. 

 A tympanic bulla 2^ inches long, very slightly discoloured with manganese. This bulla 

 closely corresponds with that of the Ziphius cavirostris from Shetland, so that I have 

 no hesitation in associating it with that genus, and most jirobably with that species. I 

 have figured it in Plate II. fig. 10, alongside of the Shetland Ziphius, so that the 

 two may be compared with each other. The South Atlantic Ocean is, therefore, a habitat 

 for this cetacean, a fact which is of interest in its bearings on the determination of the 

 zoological position of the Epiodon australe, Burmeister, from Buenos Ayres, and of the 

 Fetrorhynchus cajx'nsis, Gray, from the Cape of Good Hope, both of which I have referred 

 (p. 27) to Zipliius cavirostris. 



Station 143, lat 36° 48' S., long. 190° 24' E., December 19, 1873, 1900 fathoms. 

 A small fragment of bone was brought up by the dredge, about the size of a boy's 

 playing marble. It consisted of cancellated tissue, and was coated and impregnated with 

 manganese, and had foraminifera attached to it. It was too small a piece for one to say 

 what bone it had formed a portion of, but it was probably from a cetacean. 



Station 160, lat. 42° 42' S., long. 134° 10' E., March 13, 1874, 2600 fathoms. 

 Several tympanic bullae were found. One is figured by Mr Murray in transverse section, 

 and surrounded by manganese (PI. VIII. fig. 11). It possessed the bilobed form, but 

 the lobes were more nearly equal in size than in Mesoplodon, so that one could not 

 definitely pronounce it to belong to that genus. Two others had the Mesopdodon 

 characters, but the one had the internal posterior lobe more massive and the outer surface 

 more concave in its posterior half than the other. In one the furrow between the two 

 lobes was somewhat narrower than in Mesoplodon layardi. Another tympanic bone 

 was Delphinus. A petrous Iwne was apparently that of a Globiocej^halus (Mr Murray's 

 PL VIII. fig. 10). A nodulated mass of bone, not so big as a cricket ball, was covered 

 ■by botryoidal deposits of peroxide of manganese, and penetrated by. deposits of manganese 

 and iron, so that it was dense and of stony hardness. There were also three small frao-- 

 ments of bone, one a flat bone. 



Station 274, lat. 7° 25' S., long. 152° 15' W., September 11, 1875, 2750 fathoms. 

 A tympano-periotic bone from a Globiocephalus, figured by Mr Murray (PI. VIII, 

 figs. 4, 5); another from one of the DelphinidoB (Mr Murray's, PI. VIII. figs. 12, 13). 



