in the Arteries of slow-moving Animals. 103 



P. S. The Maucauco which you lately possessed, was suffi- 

 ciently quick in the movements of its head to snap a person's 

 finger, when touched incautiously ; and the motion of its jaw, 

 when chewing, was not slower than in other animals. A 

 Maucauco of the same species, kept among the wild beasts in the 

 Tower of London, was very apt to bite those who, calculating 

 the movements of its head by those of its limbs, approached 

 within the length of its neck: the chewing of this animal was 

 similar to that of a Cat. These external habits of motion, com- 

 pared with those of the limbs, coincide very much with the 

 internal structure here described. 



REFERENCES TO THE FIGURES. 



Plate I. 



The figure represents a dried preparation of the Lemur tar- 

 digradus, exhibiting the appearances of the arterial system. 



a, the carotid arteries. 



b, the axillary artery, dividing into the plexus described. 



c, the iliac arteries, dividing into the cylindrical ramifications. 

 The other parts of the arterial system are represented 



according to the natural and ordinary disposition. 



Plate II. 



Fig. 1, shews the axilla of the Bradypus tridactylus, dissected 

 to expose the vessels. 



a, the sterno mastoideus muscle, passing under the skin of 

 the neck. 



b, part of the axillary plexus of nerves ; the median pro- 

 ceeding along the arm, with the large blood-vessels, and giving 

 off two branches of communication with the ulnar nerve. 



