278 DR. J. MURIE ON THE ORGANIZATION OF THE CAAING WHALE. 
inappreciable in G. melas. This enormously developed sacro-coccygeus muscle is long 
and fusiform. On each side it occupies the lateral and inferior surfaces of the vertebree 
and their transverse processes from the ninth dorsal vertebra backwards; and as the 
transverse processes of the caudal elements are lost, it still continues upon them in the 
shape of a bundle of tendons continued on to the very end of the spinal column. The 
volume of its solid fleshy fibre may best be comprehended in the fact that it ranges in 
our specimen of Globiocephalus from one foot to six inches in transverse diameter, and 
with a corresponding thickness or depth. Further to particularize attachments and 
relations—it passes beneath the diaphragm, has the kidneys &c. lying upon it, and 
narrowing behind the rectum sends off, downwards and backwards, superficially, a series 
of flat tendons. These are so connected together as to constitute a very strong tendino- 
aponeurotic sheath, which spreads out and is continued on to the inferior surface of 
the broad fibrous tail. The main body of the fleshy mass meanwhile terminates in a 
single strong tendon, which passes direct along the spine, and is fixed to the very last 
vertebra. Moreover there is an appreciable flat layer of fleshy fibres, which come from 
the sides of the vertebra and spread over part of the aforesaid tendinous sheath. This 
muscular layer appears to be a kind of reduplication of the body of the muscle itself. 
A muscle the exact counterpart of the supracaudal lies on the underside of the 
transverse processes of the caudal vertebrae, and it bears the same relation to the sacro- 
coccygeus that the supracaudal does to the longissimus dorsi, save the fact of inversion 
of position. I distinguish it as the infracaudal. 
The long spinal muscles of Cetacea have received different names and significations 
from successive anatomists, though the descriptions, save that of Stannius, tally. 
Meckel' demonstrates the parts in the Narwal (J/onodon monoceros) and the Dolphin 
(Phocena communis?). His text appears to me to imply that he considers present and 
less or more differentiated :—1, an equivalent of the spinalis dorsi, biventer cervicis, and 
complexus, a longissimus dorsi, trachelo-mastoid, and splenius capitis; 2, a sacro- 
lumbalis, with cervicalis ascendens anteriorly (‘ trachélo-mastoidien, ou lintertransver- 
saire du cou” of his translators); 3, flexor caude lateralis; 4, depressor caudee =qua- 
dratus lumborum, psoas, and iliacus; 5, an inferior depressor caude. Frederick 
Cuvier? speaks of a levator caude, evidently No. 3 above. Rapp* and Stannius* coincide 
that there obtains:—a splenius capitis, longissimus and spinalis dorsi, sacro-lumbalis, 
and transversarius superior and inferior. The former thinks the great lower loin- 
muscle a psoas major; to the latter it implies more. Stannius, moreover, describes a 
caudalis superior, a caudalis inferior, a. longissimus inferior, a sacro-lumbalis inferior, 
and a set of caudal muscles unnamed by him. He also traces the short, deep spinal 
muscles, of which more hereafter. Carte and Macalister, in the Piked Whale’, have 
‘ Anat. Comp. vol. vi. p. 128 et seq. 7 Art. Cetacea, Cyclop. of Anat. and Physiol. vol. i. p. 569. 
* Op. cit. p. 83 et seq. * Mill. Archiv, 1849, pp. 22-32. 
* Loc. cit. p. 225. 
