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CHAPTER XXXVI. 



SEA-SLUGS WITH EXTERNAL LUNGS. VARIOUS GENERA AND SPECIES. 



THK 'green ACTJ];0N' AND THE CLERGYMAN. 



NUDIBRANCHIATA. 

 DORIDID^, TRITONIADiE, EOLIDID^. 



The Nudihrmichiata are so called because their gills, or 

 breathing organs, are placed outside their bodies, being 

 protected by neither mantle, nor lobe, nor shell, but con- 

 stituting every variety of ornament to the body of the slug- 

 like, but in many instances exquisitely beautiful, animals. 



As ordinary lovers of nature enjoy but few opportunities 

 of seeing these curiously constituted, and sometimes com- 

 plicated, marine creatures in any degree of perfection, it is 

 but a poor idea that is generally formed of their varied 

 beauties. Having no shells, they present no mementos of 

 their existence to the cabinets of collectors; and it generally 

 happens that our interest is not so much excited by objects 



