Translation 2783

..... 1ô3
The huge four-char.lbered }ieart is surrou)ided by a pericclx'dial
sac. 'i'he
heart is very broad and tllex'efor.e has a circular contour
The o:r'a.1 cavity of ceta.ceans is adapted only for seizing• and
holding food.
In baleen whalc:s the food is tritura:ted in tilclfirst
section of the stomach, which is a prolongation of tlli:: ,;ullet ^baleen
whales have three sections in the stomach; whcreas some
species of
tootl-l.ed whales ^beaked whales) have up to 1-j- sections).
1Sehi.nd the liver, which contains cl. biliary duct ^ there are
no bile L;lcl,ntlr3), a.:Lc the kidne,ys, which conaist of' from 150 to 500
sepa:rate lobules in dolphins and from 6,000 to 8,000 in baleen whales.
Data on the weight of various internal ort;a,ns are C2"iven in Appendix 4.
The copulatory or^a.n of males lies in a special sac, and in
110.
the relaxed state is enclosed within the whale's body;' only when the
carcass is inflated with air is it sometir,les .f'orced outside. 'i.'hé
lacteal glands ^a single pair) lie in the rear part of the abdomen,,
slightly in front of the urinogenital orifice. They become very conspicuous
only after parturition, during the periou of suckling the
young.
The females are distinguished from the males by their very
short perinaeum (st)ace between the urinogenital and anal orifices).
The cerebrum is spherical in shàpe, with Niel l•-developect convolutions
of the cerebrd.1 cortex. It is believed tha.'t the olfactory or.(;ans are
poorly daveloped, or even reduced in size; tile visual and tactile
orE,ans are much better developed. 11'he orÛari of hearing -- one of the
principal sources whirreby the animal receives ini'orniation from the
external.environment -- is highly developed.
'l'ile
auditory orifice is small, havin; the ciiiineter of an ordinary
pencil, and ter:ninates blindly, or is closed with an ea.1^-p1u8.-
^in baleen whales) .
iZhe internai structure of the ear is complex;
it is adapted to reception of both sonic and ultrasonic vibrations.
'î'hé
sonic vibrations are transferred to ti:e inner ear only tilrough
the bones of the.inner ear:
A:he foru":l.i.mL);, are mov41t,1c 011ly at t,ll. :;i.ioulder j oint.. 't't1EZr.•c
is no clavicle. ..iie .9ca.l,u7.a is reJ:a.tive:Ly ';,r.oa.a, c:acl ,,^oinetijuec has
tl.Jo. j) rOCfJl+;ïE';i., :' t1L) Spin(? Co1lti],E3tS of four rU^;]OC,:i. -`111e Cel.'ViCf-,l
vcrtebrne (of v)liich L,,cre are sovei)) are 8,rec.tly com,xes.;ed.
,.llora.ci.c verte urne becr thu ribs, from o),c t o O.i.^;,t pairs Of wi.d.ch
are jOllli;ll Lu l,l'. .ït'i11'i 111.1
inc
l ^Ile]'G ,11`i:: .I'1'c:11 tL'l', to '.;E-VI'ilteCh i.C1.l.3'0, Of