132 LUMBRICUS. 



tance behind the root of that organ, and at the root appears what is the 

 mouth. 



About sixty pencils, composed of three bristles, two of them long, 

 border each side of the body. There is considerable disparity between 

 the length of the second and the third. But these pencils do not seem to 

 indicate articulations. The course of the intestinal organ is exposed 

 throughout the whole body by the transparence of the parts. It is con- 

 siderably enlarged near the origin. 



The motion of this animal narrowly resembles that of the Nereis, being 

 undulatory, serpentine, or executed only by contortions. It appears like 

 the most minute eel to the naked eye, the setaceous pencils being invisible. 

 The bristles are in no degree recurved or hooked, as some have supposed. 



After the weeds and acquatic plants, about the roots of which those 

 animals lurk, have been withdrawn from the water, they quit the grosser 

 materials, and swim above. 



PLATE XVII. 



FIG. 6. Nais proboscidea. 

 7. The same, enlarged. 



II. LUMBRICUS. 



Kecent naturalists, subdividing the overgrown portion of the Sys- 

 tema, comprehending animals of all common features, have introduced 

 a new and numerous class under the name of Annelides. In this it is 

 proposed that those of the verminal tribes, distinguished by the partition 

 of their bodies into segments or articulations, a sanguiferous system, and 

 certain other specialties, shall be included, all combining to denote a 

 higher position in the animal scale. 



Herein numerous animals of very opposite conformation and habits 

 are associated, which, to take the subject generally, impairs the value of 

 the section. But every one must be glad to avail himself of any osten- 

 sible place where he can record the subject of his observations. 



A few species shall be described, by such as seem their prominent 



