■ CETACEA. 149 



sul)J5tance for \vliich they are principally hunted, as the body does not yield a large proportion of 

 bhibber : these cavities, however, are very distinct from the true cranium, which is rather small, is 

 placed under their posterior portion, and contains the brain as usual. It appears that cavities filled 

 with this spermaceti, or adipocire as it is called, are distributed to several parts of the body, communi- 

 cating witli those which fill the mass of the head; they even ramify through the external fat or 

 blubber. The odorous substance known by the appellation ambergris appears to be a concretion 

 formed in the intestines of the Cachalots, particularly during certain states of disease, and, it is said, 

 chiefly in the coecum. 



The species of this genus are by no means -well dcterminccl. Tliat which appears most common, the Ph. macro- 

 ccphalus of Shaw and Boiiaterre, but not of Linnaeus, has a mere callous prominence instead of a dorsal fin ; there 

 are from twenty to twenty-three teeth on each side of the lower jaw, and small conical ones hidden beneath the 

 gam in the upper : its bUnv-hole is single, and not double as in the greater number of Cetacea ; neither is it 

 symuietrical, but is directed towards the left, and temiinates on that side on the front of the muzzle, which latter 

 is truncate.* In addition to this, it is stated that the left eye is often smaller than the other, for which reason the 

 whalers endeavoiu' to attack it on that side. This species must be very extensively distributed, if, as is asserted, 

 it alone furnishes the whole of the spermaceti and amber2;ris of commerce, for these substances are brought from 

 both the north and south. Cachalots without a dorsal fin have even been taken in the Adriatic. 



The Physeters, Laccpcde, — 

 Are Cachalots with a dorsal fin. 



Two species only have been distinguished (microjw, and tursio or muJar), and those merely by the equivocal 

 character of having the teeth curved or straight, blunt or pointed. These animals are found both in the Mediter- 

 iant?an and glacial seas, in the latter of which they are reputed to be cruel enemies to the Seals. 



The ^\"HALES {Balatna, Lin.) — 

 Eijual the Cachalots in size, and in the proportional dimensions of the head, altliougb the latter is not 

 so much enlarged in front ; but they have no teeth whatever [beyond the rudiments of them in the 

 fcctal state]. The two sides of their upper jaw, which is keel-shaped, are fm-nished with thin, trans- 

 verse, serrated lamina?, termed baleen or ivhalebone, composed of a sort of fibrous horn fringed at tlie 

 edges, which serve to retain [and strain from the water] the minute animals on which these enormous 

 cetaceans feed. Their inferior jaw, supported by two osseous branches arched outwardly and upward, 

 without any armature, affords lodgment to a verj' thick and fleshy tongue, and, when the mouth is 

 clo.^cd, cuvcloi)CS all the internal part of the upper jaw and the baleen with which it is invested. The&e 

 (irgans do not allow Whales to feed on such large animals as their vast size would lead to imagine. 

 They subsist on fish, hut principally on worms, moUusks, and zoophytes, and it is said that they 

 'hiclly take the very smallest, which become entaiiglcd in the filaments of the baleen. Their nostrils, 

 Letter organized for smell than those of the Dolphins, have some ethmoidal laminae, and appear to 

 receive some small olfactory nerv'ous filaments. They have a short ccecnm. 



The Great Northern Whale (B. mysiicetiis, I.in.) was long considered to be the largest of known animals, but it 

 r.ppears from the recent observations of Capt. Scoresby, that it scarcely ever exceeds seventy feet in length, which 

 the Rorquals or AVhales with wrinkled bellies frequently surpass. It has no dorsal fin. To procure its blubber, 

 (iften se\'eral feet in thickness, and yielding an immense quantity of oil, whole fleets are annually equipped in 

 pursuit of it. Formerly bold enough to venture into our seas, it has gradually retired to the far north, where the 

 number is daily diminishing. Besides its oil, it fiiruishes the black and fiexible wludchone of commerce, the pieces 

 iifwhich are eight or ten feet long, and to the number of eight or nine hundred on each side of the palate. A 

 hundred and twenty tons of oil are obtained from a single individual. Shelled Mollusks attach themselves to its 

 skin, and multiply there as upon a rock ; the Balaiiua family even penetrate into it. The excrement is of a fine 

 red colour, and affords a tolerable dye. There is a very similar species in the Antarctic seas. 



Other species, 



The RoRauALs {Balmiopiera, Lacepede), — 



Have a dorsal fin, and are subdivided according as the belly is smooth or wrinkled. [As the former 

 section is unquestionably founded in error, as suspected by Cuvierf, \ve pass to those] which have the 

 throat and under-parts wrinkled with deep longitudinal folds, and consequently susceptible of great 

 dilatation, the intent of which, in their economy, is yet unknown. 



' U'e li.ive vcrifitH on t"'o criiiii.i lliis \vaiit of svmrnetrj in tlic i iniiuco'; us to credit the ineqiLirity of tlic eyei mcriMnnea hv Euf'de. 

 vulr;,clv aiiiiou.,cc.l l>v IJu.iluv, An J^r-...ii, and Sw.'diau-T, wLiuli I t Tl,c ^\riKUt;a btUy I.e.,, t; Mu,|;ly rilled um « ,il, « uIll'. 



