ZOOPHYTES. 413 



hair of the humau head, or of a horse's tail, if thrown into the 

 water, acquires life, and is converted into a worm. A species of 

 the Hair-worm, in Africa and the Indies, is extremely noxious. 

 It is of a pale, yellowish color, and is frequently met with among 

 the grass, especially when covered with dew. It often insinuates 

 itself into the naked feet or limbs of children and unwary per- 

 sons, where it produces an inflammation that is sometimes fatal. 

 Great care and attention are required in extracting it ; for if it be 

 broken during the operation, the part which remains in the flesh 

 continues to live, and is quite as troublesome as the whole. Some 

 naturalists consider these worms as properly belonging to the next 

 clasp 



ZOOPHYTES. 



The class of Zoophytes is the last division of the animal 

 kingdom, and the lowest in the scale of the animated creation. 

 It includes an immense number of individuals but obscurely and 

 imperfectly known, and which have but few points of resemblance 

 and connection with one another. In general they have no 

 nervous system, no complete vascular circulation, no distinct appa- 

 ratus for respiration, and no sense but that of feeling, and perhaps 

 that of tasting. This is not true, however,^ without exception ; 

 for, in some instances, traces of a nervous system, of a circulation, 

 ind of respiratory organs, may be detected, as is particularly the 

 case in the Echinodermata, the first order of Zoophytes. They 

 ire covered with a well-organized skin, and often with a sort of 

 shell with points or spines. They have an internal cavity, in 

 which are lodged several distinct intestines, and vessels which 

 maintain an imperfect circulation. There are also distinct organs 

 for respiration, and many filaments which probably perform im- 

 perfectly the functions of a nervous system. To this order belong 

 the sea-urchin, the common star-fish, the sea^egg, etc. They are 

 the most perfect of Zoophytes in their structure, and are endowed 

 with a curious set of organs for the purpose of motion. Their 

 shells are pierced with a large number of holes, regularly arranged, 

 ohrough which project the feet of the animal, or rather the instru- 

 35* 



