ON ANNELIDA. 47 



ing those animals, as it also was at the same time in regard 

 to the mollusca. 



Thus did M. Cuvier, by abandoning the views of Linnaeus, 

 return to those of the ancient naturalists, such as Aldrovandus, 

 MouflFet, and Ray, by comprehending in one and the same 

 division, the insects and worms ; but he did more, by follow- 

 ing, as he tells us himself, the ideas of Pallas, and uniting 

 with his worms, the serpulse, the sabellee, and in general all 

 the chetopodae with tubes. 



Two years after this, M. Cuvier, in the tables which form a 

 sequel to the first volume of his Lessons on Comparative 

 Anatomy, introduced a slight modification into the classifica- 

 tion of the worms, which he subsequently carried farther. 

 This consisted in comprehending under this name, in a defini- 

 tive manner, only the chetopoda and apoda, which exist ex- 

 ternally, the others, or the intestinal worms, being thrown 

 into a sort oiincerta secies, with a view to a new order. As 

 for the first, they are divided according as they have external 

 organs of respiration or not ; and the second, according as 

 they are provided with lateral setse, or destitute of them. In 

 the first, are all the chetopoda, lumbrici excepted; in the 

 second, those last animals, nais and thalassema, (now a 

 zoophyte) and in the third, the hirudines, the planarise, and 

 even the fascioli, which are nevertheless intestinal animals. 



In 1802, in a particular memoir read at the Institute, M. 

 Cuvier, in giving his observations on the organization of the 

 chetopoda, proposed to designate them as a class, by the 

 name of red-blooded worms, comprehending in it the hirudines 

 and lumbrici, without observing that the most common and 

 thickest species of our seas has not the nutritive fluid of a red 

 colour. 



A short time after this, M. de Lamarck, determined most 

 probably by the consideration put forth by Cuvier, also made 



