4go DESCRIPTION OF THE MUSEUM. 



which we often see hovering in the air on a 

 summer's evening. The class of insects is termi- 

 nated by the genus pulex (flea), which contains 

 very few species, and of which M. de Lamarck 

 has formed the order aptera. 



The collection which we have just gone 

 through occupies two hundred and four frames, 

 1 6 inches wide and il>. high, fifty-four of which 

 are filled with Crustacea, twelve with arach- 

 nides, and one hundred and thirty-eight with in- 

 sects, that is to say, twenty-six of coleoptera, 

 fourteen of orthoptera, six of neuroptera, ten 

 of hymenoptera, seventy-four of lepidoptera, five 

 of hemiptera and three of diptera. 



The annelides were formerly classed among 

 the worms, which they resemble at first sight. 

 They differ however in their organization and 

 in the colour of their blood ; M. Cuvier made a 

 distinct class of them, under the name of red- 

 blooded worms, in a memoir read to the Insti- 

 tute in 1802. M. de Lamarck has since named 

 them annelides, and his nomenclature is generally 

 adopted. 



M. Cuvier's observations upon the animals of 

 this class led him to form a separate collection 

 of them for the Museum, which has rapidly in- 

 creased in consequence of the presents made by 

 MM. Savigny and Dorbigny. M. Savigny has pre- 



