MESOPLODON. it 
Upper surface of head in front of spiracle very prominent and 
rounded, rising abruptly from the small, distinct snout. 
Vertebre.—C. 7, D. 9, L. 10, Cd. 19 ; total 45. 
1. Hyperodpon PLANIFRONS, Power (1882). 
Southern Bottlenose Whale. 
This species is only known from a mutilated skull found on the 
beach of Lewis Island, Dampier’s Archipelago, and described at 
length by Prof. Flower in the Proceedings of the Zoological 
Society for 1882, p. 392, who figures the upper surface and the 
side view of the skull. 
Genus 1V.—MESOPLODON, Gervais (1850). 
A mandible with a much compressed and pointed tooth on each 
side, variously situated, but generally at some distance behind 
the apex ; its point directed upwards and often somewhat back- 
wards, occasionally developed to a great size. Skull not greatly 
differing from that of Hyperoddon. Anteorbital notch not very 
distinct. Mesethmoid cartilage ossified in adults, coalescing with 
the surrounding bones of the rostrum, which is long and narrow. 
Two or three anterior cervicals united, the remainder usually free. 
Vertebree.—C. 7, D. 10, L. 10 or 11, Cd. 19 or 20; total 46 to 48. 
1. MrsopLopon LAYARDI, Gray, sp. (1865). 
Long-toothed Whale. 
Mandibular tooth strongly compressed, with the apex everted, 
and seated upon a flat strap-like base, which grows upwards, 
backwards, and finally inwards, closing in adult males (?) over the 
upper jaw, and sometimes actually meeting. Lateral basirostral 
groove slight. Premaxillary foramen level with the maxillary. 
Dimensions.—Up to about fifteen feet. 
Habitat.—New South Wales ; Cape Seas. 
References.—Gray, B.M. Catal. Seals and Whales, p. 353, fig. 
72. a., b. (skull and lower jaw); c. (mandibular teeth from the front); 
Scott, Seals and Whales, p. 117. 
Note.—In Mr. Krefft’s MSS. occurs a notice of a Ziphiid Whale, 
which he names J/. thomsoni, but which is probably the female of 
this species. It was stranded at Little Bay, near Sydney. 
2. MESOPLODON DENSIROSTRIS, Llainville, sp. (1817). 
Massive-toothed Whale. 
Mandibular tooth with the apex directed vertically, placed on 
a very massive base, which is implanted in a greatly expanded 
alveolar margin of the jaw, not found in any other species. Lateral 
