45 



examined by HAUSSMAN, who found, that they 

 absorbed oxygene gas and returned carbonic 

 acid. He even examined the respiration of some 

 worms, and perceived, that they also changed 

 oxygene gas into carbonic acid. SPALLANZANI 

 had observed the same long before, but he also 

 believed that several of the mollusca absorbed 

 nitrogene gas, a circumstance, which we must 

 call in question, till it is confirmed or rejected 

 by further chemical experiments. 



I have already remarked, that that portion of 

 the blood, which goes to the reproduction of the 

 various parts of the body, is void of colouring 

 matter, and penetrates the last fine ramifications 

 of the arteries, from whence it cannot afterwards 

 be returned, but must exude through the open- 

 ings of the capillary vessels. Just at this point 

 those parts are generated, which are to be repro- 

 duced, whereupon the remaining part is either 

 absorbed by a particular system of vessels-, which 

 from their functions bear the name of absor- 

 bents, or discharged by means of secretions and 

 excretions. These vessels are placed in all part* 

 of the body with their absorbing extremities 

 open, and take up not only the remainder of the 

 imcoloured blood after the reproduction, but also 



