DESTRUCTION OF BIRDS. 101 



tribe are here represented by small calcareous pieces which surround the 

 mouth. The respiratory apparatus of the Holothuridce is remarkable, and 

 differs from all other animals; like the Asteridce and Echini, the sea-water 

 is freely admitted into the interior of the body, but in this class instead 

 of bathing the surfaces of the viscera, it is collected in a peculiar set of 

 ramifying canals. The circulatory system of these animals is, like that of 

 the Echini, but imperfectly understood, and various authors give different 

 accounts of its arrangement. The generative system corresponds with that 

 of the Asteridce. The nervous apparatus is but obscurely developed, and 

 the only sense the Holothuridce possess is that of touch, by means of the 

 tentacles placed round the mouth. 



The Fistularidce, the last of the class Echinodermata, are animals covered 

 with a delicate cuticle or skin, with a strong muscular development beneath; 

 like the last, they are furnished with tentacles round the mouth. The 

 structure of the alimentary canal of this tribe corresponds with that of 

 the Holothuridce; the intestine is very long, and the anal orifice is situated 

 high up in the body, an arrangement well adapted to the habits of the 

 animal, (Siponculus,) as, if placed in the usual position, the excrementitious 

 food cast out, which consists of sand and broken shells, would soon fill 

 the cavity occupied by the animal. The circulatory system is essentially 

 analogous to that of the Echinodermata. Their nervous system is more 

 complete than anything we have yet met with; and two small ganglionic 

 masses can be detected; and as to their organs of reproduction, nothing 

 decisive or satisfactory has yet been made out. 



Uppingham, February 9th., 1857. 



(To be Continued. J 



. ON THE DESTRUCTION OF BIRDS. 



BY THOMAS FULLER, ESQ. 



I am very happy in seeing so valuable a contributor to "The Naturalist" 

 as Mr. 0. S. Round, joining in deprecation of the lamentable work of 

 destruction now prevailing towards the feathered creation, through mere 

 wantonness and superstition. All lovers of nature will unite in this feeling, 

 whatever difference of opinion may exist upon the difficult question "How 

 far their destruction is necessary?" 



Mr. Round expresses his fears of undue increase if natural checks were 

 removed. Are not these "natural checks" seriously interfered with in pro- 

 tection of game, by the destruction of every description of bird of prey, 

 in which protection do not all the numerous small birds constituting the 

 pilferers so annoying to the husbandman share? If undue increase detrimental 



VOL. VII. 



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