Cetacea. MAMMALIA. Cetacea. 
cxxx 
THE GREAT-HEADED CATODON [Catodon macro- 
cej')halus) — Plate 27, li"'. 87. — Physeter maci'oceplia- 
lus of Flower. Iiiliabits tlie tropical seas, and isacci- 
dentiilly in temperate regions. Flower regards tliis 
as identical with the <J. australis. According to 
Maury, the Sperm Whale never doubles the (Jape of 
Good Hope, but does pass around Cape Horn. 
Hence he infers that there may be a warm under- 
current off the latter point. 
Meganeuron. — Gray. 
'rids genus has a sub-circular atlas vertebra, rather 
broader than hii>h- 'I'he central canal sub-circular, 
in the middle of the body, and widened above. 
'The rest of the animal is unknown. “It is jdaced 
among the Gtitodontidcc because this family is the 
only one that has the atlas separate from the cervical 
vertebrai, and of the sim[)le form.” — Gray. 
KREFFT’S CATODON [Meganeuron Krefftii, Gray). 
— 'I’his is an Ansti’alian species. 'I.’he atlas is given 
as measuring thirteen inches in width. 
Family— PHYSETERIDJE. 
The head in this group is depressed, and rounded 
in front. 'I’he blowers are linear, the left one often 
obliterated, and situated on the back of the fore- 
head. 'J'he mouth is small, iiPerior and rounded. 
'I'he dorsal fin is compressed and falcate. The skull 
is short, crown concave, the hinder portion of the 
wall formed by the maxillaries, and divided, as it 
were, into two sub-equal iiortions by a central bony 
ridge, which is more or less twisted towards the right 
side. 'The upper jaw is toothless. 'The atlas and 
cervical vertebrae are all united into a solid mass. 
I^HYSETEE. — Gray. 
'I’he head is large and rather depressed in this, the 
typical form. It is only known from Sibbald’s 
description, which, says Gray, is rather specific, as is 
usual with his descri[)tions, and are very correct. 
Mr. Flower doubts the accuracy of it. In the fam- 
ily Physeteridm are three genera, viz. : Physeter, 
Kogia and Euphysetes. Of -the first-named, one 
species — the only one — is an inhabitant of the 
North Sea. 'I’hree species belonging to the other 
two genera are found in the waters of Indian Ocean 
and Australia. Sub-order Susuoidea is re[)resented 
wholly in India. 
■Sub-Order — DEEP H 1 NOIDEA. 
'I’he well-known Dolphins are included in this 
group. The characi eristics are seen in the two nos- 
trils muting into a single central transverse or cres- 
centic blower, on the back of the crown. 'I’he teeth 
are permanent in both jaws, or rarely deciduous by 
age. 'I’he head is generally produced in a beak-hke 
form. 'I’he dorsal fin is sometimes wanting, and is 
falcate or sickle-shaped when present. 
A species belonging to the genus Inia — -the only 
one of the group — is found in the Amazon River. 
'I’he family Deljihinidm is arranged by Dr. Gray to 
include tribe Stenoyima, with nine species of genus 
Steno, all of the Indian Ocean and South Seas, 
save one from the North Sea. Genus Sotalia, with 
one species, is known to the waters of British 
Guiana. 'This family also includes tribes Delphi- 
nina, Lagenorhynchina, Pseudorcaina, and Phocm- 
nina. 'I’he first of these tribes embraces the famil- 
iar typical forms, the true Dolphins — Delphiims, 
with ten species, five being known in our Amer- 
ican waters. ’I’he genus Olymenia includes four- 
teen species, two being known to waters of South 
America and one to the North Sea. Genus Delphi- 
napterus has one species, common to South Atlantic 
and New Guinea. Genus 'I’tirsio has seven species. 
One is found in Philadelphia Harbor, and was de- 
scribed by Prof. Cope as Delphinus erebennus, and 
subsequently as D. tursio. One other species is 
known to waters of Buenos Ayres, South America. 
Entropia has two species in the South Seas. In 
the tribe Lagenorhyncliina, genus Electra has seven 
species, one of which is native to the west coast of 
North America, named E. thicolea. Genera Feresa, 
Leucopleurus and Lagenorhynchus have each one 
si)ecies. • Of tribe Pseudorcaina, two genera are 
enumerated, each having two species. 'I’ribe Phocce- 
nina includes genera Phocasna, Acanthodelphis and 
Neomeris. Phoemna is North American, and Acan- 
thodelphis known to Brazilian waters, each having 
one species only. 
THE COMMON DOLPHIN [Pelphinus delphis) — 
Plate 28, fig. 88. — Historical and classical, the Dol- 
phin has in all ages claimed a good degree of interest 
and attention from the general reader, as well as 
from the poet, the painter and the savant. It is 
graceful in form, and has long been the ideal of 
beauty in certain artistic groupings and designs. 
'I’he characteristic prominence on its head, with its 
prolonged snout, is exaggerated somewhat to produce 
the conventional art form. Yet, what with its grace- 
ful movements and attractive markings, it may well be 
regarded as exceptionally interesting. This is the 
true Dolphin of the poet and the painter, although 
the sailor may claim that the fish, so called, which 
exhibits most brilliant colors, made changeable 
while dying by certain aspects of the circulation of 
the blood, is also the true one. 'I’he latter has some- 
what the same outline of head and shoulders ; but 
the former, also, has the elongatml flexible body, 
with the elegant forked tail, whose flidces add such 
grace to the drawings of ancient works. 'I’liough 
fannliar to the reader by description and illus- 
tration, yet the Dolphin is seldom seen alive. 
An excellent opportunity was offered during the 
winter of 1878 at the New York Aquarium. 
A specimen, measuring about seven feet in length, 
was captured in the East River, New York, 
and was successfully exhibited alive during several 
months. Jt was regarded as much more interesting 
than the Beluga, or White Whale, which occupied 
the great tank at nearly the same time, the latter 
being sluggish, compared with the Dolphin, whose 
graceful and active manoeuvres were a souice of 
great pleasure to the many visitors. 'I’his creature is 
regarded by sailors as remarkably swift, and it has 
