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sea-blubber, in which certain vessels radiate from 

 the stomach directly to the circumference of the 

 body, where they open into a circular tube ; but 

 of the ultimate distribution of the fluids so car- 

 ried we are entirely ignorant. In all probability 

 these vessels collectively partake of the nature, 

 not only of intestines, but at once of veins or ab- 

 sorbing vessels and of arteries ; the former of 

 which, in the higher classes of animals, serve to 

 convey the blood to the centre of the circulation, 

 and the latter to carry it to every part of the 

 body. These two systems of vessels are for the 

 first time quite distinct, as well from each other, 

 as from the intestinal canal, in the earth-worm, 

 in which one large vessel, apparently the chief 

 artery of the body, runs along the back from the 

 head to the tail, and two others, which seem to 

 be veins, and one of which traverses in its pas- 

 sage the respiratory organs, along the lower part 

 of the body again from the tail to the head, the 

 two sets of vessels being connected together, 

 about the neck of the animal, by several half- 

 hoops, which meeting, encircle the. beginning of 

 the intestinal canal. Hitherto there is no heart, 

 properly so called ; but the half-hoops just men- 

 tioned, being not entirely tubular, but composed 

 of strings of little rounded hollow bodies, which 

 appear to be capable of contracting, and thus 

 propelling their contents onwards, have been pre- 

 sumed to consist, as it were, of a series of little 

 hearts, all conjointly performing the office of one 

 great one. A distinct heart, however, as well as 



