NATURAL HISTORY. 195 



And as he pranced before, still seeking for a snake, 

 s who 

 I might 



, , 



As who would say, ' There is none here, I trow, will me forsake ' ; 

 perceive a wolf, as white as whales-bone." SURREY. 



583. Why is the enormous size of its head no impediment to 

 rapid locomotion ? 



Because, being very light in proportion to the rest of the body, 

 it serves rather to buoy up the animal, and to act in the nature of 

 a balloon upon the vast mass with which it is connected. 



584. In the spermaceti whale the great part of this bulk is made up of a large, thin 

 membranous case, containing: during life a thin oil, of much less specific gravity than " 

 water, below which, again, is the substance called the "junk," which, although 

 heavier than the spermaceti, is still lighter than the element in which the whale mo veth. 

 Consequently, the head, taken as a whole, is lighter specifically than any other part of 

 the body, and will always have a tendency to rise, at least so far above as to elevate 

 the nostril, or " blow-hole," sufficiently for all purposes of respiration ; and, more 

 than this, a very slight effort on the part of the fish only would be necessary to 

 raise the whole of the anterior flat surface of the nose out of the water. In case 

 the animal shorjd wish to increase its speed to the utmost, the narrow inferior 

 surface of the head, which bears a strong resemblance to the cutwater of a ship, and 

 answers the same purpose to the whale, would be the only part exposed to the 

 pressure of the water in front. Thus, he would be able to pass with the greatest 

 celerity and ease through the boundless track* of his wide domain. 



585. WTiat is whalebone? 



The substance known under this name, sometimes called baleen, 

 is found in the monstrous mouth of the Balcena mysticetus, or 

 whalebone whale, where it forms the substitute for teeth, of which 

 otherwise the animal is destitute. 



586. The whalebone depends vertically, or nearly so, from the palate like a port- 

 cullis ; is rather elastic ; and its lower points are received by the tongue and lower 

 gums. Its function is to act like a sieve or strainer, or perhaps in the nature of a 

 mill, reducing the food which flows into the open mouth of the whale to a state 

 proper for digestion. It consists of an immense number of fibres slightly soldered 

 together, and covered with an epidermis (cuticle or skin). The maxillary 

 (jaw) and palatial (palate) bones of the whalebone whales form on their interior 

 surface two inclined planes, which are concave, but resemble slightly the roof of a 

 house inverted. It is to these bones that the blades or plates of whalebone are 

 attached. They are widest at a point of the mouth which is nearer to the bottom of 

 the gape than to the snout; and they diminish hi size as they approach both 

 excremities. They are attached to the bone by an elastic cartilaginous substance. 

 The plates of the whalebone move upon these elastic hinges. When the mouth ia 

 shut, these blades lie or* over the other like the folds of a fan, or the leaves in 

 flower -bud. 



