236 ON THE CETACEAN GENUS MESOPLODON. [Feb. 28, 



EXPLANATION OF THE PLATES. 

 Platk XII. 



Fig. 1. Upper surface of cranium of Mesoplodon grayi, Haast, type, J nat. size. 



lak,\b. Transverse sections of the rostrum of the same at a and b respec- 

 tively, nat. size. 



2. Outline transverse section of M. haasH, Flovcer, after Flower, for com- 

 parison with the sections 1 a and 1 b, nat. size. 



Pf.ATE XIII, 



Fig. 1. Upper surface of cranium of Mesoplodon grayi, Haast — the Kaiapoi 

 skull (I), \ nat. size. 

 1 a & \b. Transverse sections of the rostrum of the same at a and b respec- 

 tively, nat. size. 



2. Outline transverse section of M. australis. Flower, after Flower, for 



comparison with the sections 1 a and 1 b, nat. size. 



Plate XIV. 



Fig. 1. Transverse section of rostrum of Ziphiits cavirostns, 5- 



2a&2b. Transverse sections of the rostrum of a young individual of 

 Mesoplodon grayi, Haast. Cf. fig. 1, page 221. 



3. Outline trans' erse section of the rostrum of M. grayi, Haast, in tha 



E. Coll Surgeons, after Flower. 

 4« &4b. Transverse sections of the rostrum of M. grayi, Haast, §, in 



Canterbury Mus., Christchurch, N.Z. 

 5. Transverse section of the rostrum of M. grayi, Haast, 2 , in the Otago 



Univ. Museum, N.Z. 



Fig. 1 is I nat. size ; figs. 2-5 nat. size. 



Plate XV. 



Figs. 1, 2. Transverse sections of Mesoplodon grayi, Haast — Specimen E in 

 list above, from the Chatham Islands, nat. size. 

 3-5. Transverse sections of M. grayi, Haast— G in the list above, from 

 the Chatham Islands ; fig. 4 is the most anterior and 5 the most pos- 

 terior section, and all are of the nat. size. 



Explanation of Abbreviations. 



br.g. Basirostral groove. 



butt. Maxillary buttress. 



gib. Gibbosity. 



mr. Mesorostral bone. 

 mr.s. „ suture. 



mr.cr. „ crease. 



Tnx. Maxillary bone. 

 , mx.f. „ foramen. 



mx.i. „ ingrowth. 



meth. Mesethraoid bono. 



meth.s. Anterior termination of mesethmoid bone. 



pmx. Preniaxillary bone. 

 pmx.s. „ suture. 



pmix.o. „ ossification. 



pmx.f, „ foramen. 



s.oc. Supi'aoccipital bone. 



v. Vomer. 



v.s. Vomerine suture. 

 V.tr. „ trough. 



