292 M. Nicolucci on the Anatomy of the Triton aquaticus. 



branch directing itself in a great measure to the skin of the 

 muzzle and to the internal parts of the eye, the second to the 

 maxillary angle, and the third partly to the skin of the head 

 and partly to the inside of the mouth. The eighth pair or 

 the acoustic, rising immediately from the brain, and in con- 

 tact with the calcareous granules, enters into the auditory ca- 

 vity ; and the ninth or the pneumo-gastric, having a common 

 origin with the fifth, at first enlarges into a ganglion, then 

 resolves itself into three branches ; the outer directed to the 

 skin, the inner to the heart and the aorta, and the median 

 further parts into two branches, one for the stomach and the 

 other for the lungs. 



2. Circulating System. 

 A. Arterial System. — From the conical ventricle of the 

 heart, placed above a single (? double) auricle, rises the bulb of 

 the aorta, whicli sends out three great trunks from both sides : 

 the upper of which may take the name o^ carotid, since it en- 

 tirely distributes itself in the head, and at first sends a super- 

 ficial branch into the interior of the mouth, then another which 

 soon divides into two ; the internal, which supplies a branch 

 to the eye and enters the cranium, passing over the brain and 

 anastomosing with the opposite branch ; and the external, 

 wholly directed to the ear. The last most conspicuous branch 

 is the maxillary, which supplies also a small branch to the 

 muscles of the neck. The third or lower trunk, having anasto- 

 mosed, by means of a transverse branch, with the median, is 

 directed entirely to the lungs, where it forms a very delicate 

 network joined by its extremities with the ramifications of the 

 pulmonary vein. The median trunk is that which makes a 

 curve and then descends to form the aorta ; but before it bends, 

 a little after its quitting the bulb, it sends out a branch which 

 turns directly towards the nasal fossaj, supplying besides a 

 ramuscule to the eyeball. The aorta, which runs through the 

 whole body to the extremity of the tail, furnishes from its 

 commencement in opposite directions the subclavian arteries, 

 which branch off in their turn into the brachial, ulnar and 

 radial, terminating in the four digitals for the upper limbs, 

 before they enter which they furnish a large branch [arteria 

 mammaria) anastomosing with the ischiatic arteries, and from 

 which separate so many ramusculi for the abdominal muscles 

 and skin. Thence from the aorta there rises lower down the 

 coeliac artery, from which originate all the arterial vessels of 

 the abdominal cavity. Because there arises from this the cysto- 

 hepatic artery directed towards the gall-bladder and to the 

 liver, where it is dispersed in a multiplicity of branches ; the 



