230 Zoology and Comparative Anatomy 



teenth, which is the smallest. The appearance of the chest 

 as a whole will give the spectator a very good idea of the 

 framework of a small sailing vessel ; and it is impossible to 

 form any accurate idea of the dimensions of this cavity, with- 

 out making an examination of the interior : there only it is 

 that a true conception can be formed. 



The Sternum or Breast-bone, — This bone, when contrasted 

 with the immense dimensions of the chest, is very small and 

 spongy in its texture ; and the layer of compact osseous tissue 

 covering it is so thin as hardly to be perceived. The shape 

 bears some rude resemblance to a cross, the apex or top of 

 which is carried forward. This bone gives attachment to the 

 first rib on each side, and is composed of three bones con- 

 nected by cartilage. It has two plain surfaces, and exhibits 

 nothing else worth mention. 



o ^^ 



The Bones of the Pelvis. — The pubic bones, which I have 

 already cursorily mentioned, may not unaptly be considered 

 as appendages of the spine. They are extremely small, and 

 each has somewhat a triangular shape ; but one of the angles 

 is elongated upwards, and they bear altogether no small 

 resemblance to the marsupial bones found in the kangaroo 

 and other animals of New Holland, &c. They are found float- 

 ing in the muscular walls of the abdomen ; and the only con- 

 nection they have with each other is by a very loose ligament. 

 From their position, they, as far as we can perceive, can be 

 of very little service to the animal, inasmuch as they neither 

 possess size nor strength sufficient to protect the generative 

 organs, or to guard, during the pregnant state, the foetus 

 within. However, there is not the least doubt but these bones 

 must answer some important purpose in the animal economy, 

 else the allwise Architect of the universe would never, in his 

 wisdom, have constructed an organ insubservient to some 

 useful function. 



THE ANATOMY OF THE THORACIC EXTREMITIES, OR PECTORAL 



FINS. 



The whale being deprived of clavicles, or collar bones, 

 the pectoral fins are composed of the shoulder-blades, and 

 what are, strictly speaking, the pectoral fins. 



The Scapula or Shoulder-blade, — This is placed on part of 

 the last cervical vertebra, and partly on the first dorsal, which 

 it partly covers ; it is a very large bone, of which the supe- 

 rior part is semicircular, and the inferior nearly quadrangular. 

 The external surface is extremely smooth : there is no spinous 

 process ; but one, analogous to the acromion process of other 

 animals, projects about 15 in. beyond the neck of the scapula. 



