SiKENiA. MAMMALIA. Maesdpialia. 
cxxxu 
Sub-Order — ZIPHIOIDEA. 
In this group the liead is produced in the form of 
a beak like tlie preceding. 1’he teeth are only in the 
sides or front of tlie lower jaw, and fit into sockets 
in tlie upper one. 
Family IIyperoodontid.® includes genera Hy- 
peroodon and Lagenocetus. A species of the 
first, the II. semijunctus, was described by Cope 
in Proc. Acad. Nat. Set., Phil., 1865. Habitat, 
Charlestown Harbor. One species only of the 
Lagenocetus is known, its habitat being in the 
North Sea. 
Family Epiodontid^ has two genera. Epiodon, 
the typical genus, has two species, one an inhabitant 
of South American waters. 
Family Ziphiid;e includes four genera, and is found 
in the British Channel. 'I'lie genera Dolichodon. 
Neoziphius and Dioplodon are the remaining groups 
of this family — each with one species. 'I’he latter. 
D. schellensis, is a most remarkable creature, if we 
may judge from the skeleton, a figure of which Ur. 
Gray gives in the work from which we have extracted 
our account of the Cetacea. 'J'he skull is totally 
unlike anything of similar uses, and is increased in 
singularity by two horn-like processes projecting 
from each anterior portion of the snout. 'I'he verte- 
brae are enormous in comparative size, and have e.x- 
tremely high and broad spinous processes, while the 
ribs are slender and short, the whole aspect being 
that of a body of great muscular strength in the 
region of the spinal column, and one very weak or 
contracted in the visceral regions. 
Family — MANATIDHU. 
The animals arranged under this family name, in 
the principal portion of this work (vol. i, p. 205), are 
now arranged by authors in a separate order. Owen 
places them between the Pachyderms and Cetaceans, 
in order Sirenia. An account of their structure and 
habits will be found as above. This is a small but 
remarkable group of animals. 'I'he Seals are regarded 
as carnivorous marine animals ; the present are herbi- 
vorous, and resemble the thick-skinned creatures of 
the land. 'I'hey feed chiefly upon the succulent veg- 
etables that grow upon the borders of the lakes or 
rivers wdiere they reside — crawling out, like the 
Alligator, to sun themselves or browse upon the veg- 
etation that grows a little removed from the shore. 
THE MANATEE [Manatus latirostris). — This crea- 
ture is nearly confined to the small area covered by 
the West Indian Islands and the gulf shores ot 
Florida and Mexico. 'I’ampa Bay, in Florida, is a 
favorite resort for them. 'I'he Manatees are arenfari- 
ous, and at one time were very abundant. Barton 
records instances of great numbers being killed by 
the Indians of Florida. They are now comparatively 
rare. 'I'his species of Manatee was kept alive in Cen- 
ti'al Park, but died on the approach of cold weather. 
Another species, M. australis (Plate 36, fig. 84), is com- 
mon to the waters of South America. A very interest- 
ing species was discovered by Steller during his voyage 
to Behring’s Island. 'I'his has since become extinct. 
It is named Steller’s Rhytina (R. stelleri), Plate 26, 
fia- 86, where a full account will be found. Another 
genus, the Halicore, is known in the Indian Ocean. 
Order XIIL— MARSUPIALIA. 
'I’his order well-nigh belongs to another continent, 
a few species of Opossums, including one notable 
creature — the Virginia Coon, and others are known 
in South America. 
Wallace records three genera and twenty-two 
species of the family Didelphyidoe. 
'I’he range of the true Opossums in America — and 
they are regarded as peculiar to this continent — is 
from the southern boundary of 'I’exas to the river 
la Plata, and on the west coast to latitude 42° south. 
One species only is found above, and that extends 
from Florida to the Hudson River. 'I’he species is 
most numerous in the great forests of Brazil. 
E.ktinct Didelphyid^ are found in the caves of 
Brazil, but none in the older formations. 'I’he' living 
species only has been found in the Post Pliocene 
deposits. “In Europe many small species have been 
found, which are named in a distinct genus, Pera- 
therium. 'I’hey were discovered in the various 'I'er- 
tiary deposits, from the Upper Miocene to the Upper 
Eocene.” — Wallace. 'I’his author concludes that 
“ sufficient evidence has been shown that American 
Marsupials have nothing to do with those of Aus- 
tralia, but were derived from Europe, where their 
ancestors lived during a long series of ages.” 
THE VIRGINIA OPOSSUM [Didelphis 'oirginiana) 
— Plate 30, fig. 96. — 'I’he ’Possum of the Southern 
States is too well known and quite too unique among 
other animals of our continent to require special 
mention. A good account of this species, with notice 
of several others, including the curious form called 
Yapock (Cheironectes variegatus), fig. 92, known 
in South America, may be found in vol. i, page 
217. 
'I’he last remaining order embraces only the few 
forms called, respectively. Dutch-billed Platy[)us and 
Porcupine Ant-eaters. 'I’his order — Monotremata — 
does not, therefore, concern us, as they are all Old 
World animals. 
