124 HERBIVOROUS CETACEA. 



in general open externally on the top of the head, which enables 

 the animal to breathe the air without raising his muzzle out of the 

 water, and the larynx is advanced to the posterior nares, so as to 

 establish, independently of the pharynx, a communication be- 

 tween the nasal fossae and the lungs, and permit him to fill his 

 mouth with water, and swallow his food without interrupting 

 respiration. The stomach of the Cetacea generally presents as 

 great, if not greater, complication in its structure, than that of the 

 Ruminants. There is no large intestine recognised, and their 

 teeth, when they exist, are all alike. 



25. This order is composed of two families which are distin- 

 guished by their regimen, their teeth and several other peculiari- 

 ties of organization, and may be recognised by the position of 

 their nares ; they are : 



1st. The HERBIVOROUS CETACEA, Cetacea Herbiuora, the 

 nares of which open externally at the extremity of the muzzle ; 



2d. The ORDINARY CETACEA, or BLOWERS, Cetacea Ordinaria, 

 the nares of which open on the posterior face of the head. 



FAMILY OF HERBIVOROUS CETACEA. 



26. The food of these animals being herbaceous, they possess 

 molar teeth with flat crowns, and the faculty of crawling on land, 

 to graze along the sea shore : their anterior extremities are more 

 flexible than those of other Cetacea, and they do not frequent 

 the high sea. From the circumstance of grazing like Ruminants, 

 and being large and massive, travellers often designate them 

 under the names of Sea-utl, Sea-cow, and Sea-calf. Sometimes 

 they are termed Mermaids, Sea-women, and it is probable 

 these have been in question, when some modern navigators said, 

 they had met with Sirens and Tritons : for they have a habit of 

 often raising the anterior part of the body out of the water, and 

 their mamma? being on the chest, tfie hair which surrounds the 

 snout, might at a distance appear like female tresses ; and then 

 the adroitness with which they sometimes use their fins to carry 

 their young, gives them in certain points, some remote resem- 

 blance to the human species. Their stomach is divided into four 

 pouches, two of which are lateral. 



27. The principal genera of this family are the Lamantins and 

 Dvyonns; 



28. The Lamantins, Man atm, have an oblong body termi- 

 nated by an elongated oval fin. Vestiges of nails are found on 



25 How is the Order of Cetacea divided ? 



26. What kind of teeth have the herbivorous Cetacea ? What are Mer- 

 mai Is? What is the character of the s'omach of Herbivorous Cetacea? 



27. What are the principal genera of the family of Herbivorous Cetacea 7 



28. What are Lamantins? Why have they been called Manati? 



