1893.] CETACEATf C4ETS"ITS MESOPLODOTf. 217 



which the first appearance of change in the mesorostral groove is 

 visible. 



B. A damaged cranium, without its mandible, received from the 

 Chatham Islands, and now exhibited ; of unknown sex, and of a 

 more advanced age than A, The vomerine trough is still empty 

 and perfectly smooth. It would appear to be about the same age, 

 being apparently about the same stage of development, as Meso- 

 plodon f/rai/i, Haast, figured by Van Beneden and Grervais iu their 

 ' Osteographie des Cetaces.' 



C. A skeleton in the Museum of the Royal College of Surgeons — 

 that described and figured by Sir W. Plower as M. grayi, Haast, 

 in his paper already cited. This is the second of the two Salt 

 Water Creek skeletons prepared by Sir J. von Haast, and deter- 

 miued by him to be Oulodon grayi. Its sex is doubtful ; but it is 

 still quite young, as the interior of the vomerine spout (so far as 

 unconcealed by the rostral iutegument on the auterior part of the 

 snout and of the dried cartilage in the canal) is still smooth and 

 free from ossification. 



D. The rostrum of a specimen obtained for me from the 

 Chatham Islands, and now exhibited. I have no doubt it belongs 

 to the species Mesoplodon grayi, Haast. Its sex is unknown, but 

 its age is somewhat greater than any of those already mentioned. 

 The vouierine trough is partially filled with osseous tissue. 



E. The rostrum of a third speciuien from the Chatham Islands, 

 and now on the table, of unknown sex and of a still more advanced 

 age, but still immature. This specimen, along with B, D, and G, 

 mil be presented to the British Museum. 



F. A skull, with its mandible, of an immature (according to 

 Haast, female) specimen of Mesoplodon (Oulodon) grayi, Haast. 

 This is the second of the three skulls described by him in the ninth 

 volume of the ' Transactions ' of the New Zealand Institute from the 

 Chatham Islands, and now in the Otago Museum, Duuedin, N. Z. 

 It is also a co-type of the genus and species Oulodon grayi. 



G. The rostrum of a cranium obtained for me from the Chatham 

 Islands. It is still immature, as the mesorostral furrow, though 

 nearly full of ossified tissue, is not yet quite filled up, and the 

 whole of the bones are still spongy. It belongs undoubtedly to 

 the species grayi, Haast, of this genus, 



H. A complete female skeleton of 3Lsoplodon (Oulodon) grayi, 

 Haast, one of four individuals that in December 1876 ran on the 

 beach near Salt "Water Creek, north of Banks Peninsula, N. Z. It 

 was identified and described as the co-type of Oulodon grayi by 

 Sir J. von Haast. Of these four specimens two skeletons were 

 prepared — one (C) being sent to the Royal College of Surgeons, 

 London, and the present specimen retained in the Canterbury 

 Museum, where it is now. Though described by Sir J. von Haast 

 as "a full-grown animal," it still bears marks of immaturity in its 

 incompletely filled-np vomerine spout and in the rostral bones 

 exhibiting none of that ptitrosal density so characteristic of fully 

 adult Mcaoplodoiita. 



