LUTRA VULGARIS. 71 



The Otter [Lutr a vulgaris, Erxl.]. 



The hair is of two kinds ; a long and strong hair, and a short and soft 

 hair, which thickens it ; and the short is defended hy the long hair. 



The external ears are very small and flat. The tongue is not rough 

 like a cat's, and has no worm. 



The edges of the epiglottis terminate between the arytenoid and the 

 inside of the thyroid, so that there are two ligaments joining from the 

 arytenoid and thyroid ; the uppermost is the mouth, as it were, of the 

 sacculus laryngis : this is not large, much as in the human. The 

 trachea is round, so that the edges of the cartilages meet, and when 

 they are squeezed they overlap one another : their edges are thinned for 

 this purpose. It has the oesophagus behind it at the upper part, but at 

 the lower part it is a little on the left. Where it passes behind, the 

 trachea is a little flattened by the left edges of the cartilages continued 

 some way within those of the right, as (~^ . 



There are two very small thyroid glands some way from the trachea, 

 and a very large thymus. The anterior mediastinum is very thin and 

 broad, and is perforated with many holes like lace. The membranes 

 that pass between the pericardium and diaphragm are very loose when 

 the lungs are in a flaccid state, which allows of their dilatation : they 

 are united anteriorly to the mediastinum. The right one is united pos- 

 teriorly to the vena cava ; the left posteriorly to the oesophagus. The 

 posterior mediastinum is double, from the basis of the heart down to the 

 diaphragm ; above that it does not so much deserve the name. The 

 cavity of this doubling contains nothing. The pericardium is very thin 

 and transparent. 



The heart has (I imagine) no foramen ovale, for no injection got 

 from the right into the left auricle. There is no fat upon the heart, 

 although the animal itself was very fat. 



The lungs seemed to be divided into three lobes on both sides : the 

 right side seemed to be as common ; but, on the' left, and backwards, 

 there was ho cavity ; this I had destroyed before I observed it : I imagine 

 that this held the third lobe on the left. There were two lobes on the 

 left side, and three on the right (in another subject). The third lobe is 

 the middle or azygos lobe ; they are very elastic, and firmer in texture 

 than common : they sink at once in water. Is this peculiar to diving 

 animals 1 ? 



1 [In an otter I dissected at the Zoological Gardens, the left lung had two lobes, 

 and the right lung four lobes. The position of the lobulus medius or impar probably 

 deceived Mr. Hunter in his first dissection. All the lobes swam in water ; they were, 

 however, gorged with blood, the animal having been drowned under the ice of its 

 pond. The pulmonary veins were distended with coagulum.] 



