MYUIAFOUA. 249 



the assertion of De Gecr, who says that he only found three 

 pairs and eight annuli in the young animal — but is it certain 

 .that this change of which Savi speaks is really the first, and 

 should v/e not, on the contrary, rather presume that these 

 young individuals do not suddenly pass from a state in which 

 they exhibit no locomotive appendages to one where we find 

 them possessed of twenty-six pairs, or in a word, that previ- 

 ous changes of tegument, which have escaped the notice of 

 Savi, have taicen place and successively developed this num- 

 ber of feet? Do not the observations of the Swedish Reau- 

 mur confirm these gradual transitions? Be this as it may, 

 the first eighteen pairs of feet, according to Savi, alone serve 

 for locomotion ; at the second change we observe thirty-six 

 pairs, and at the third, forty-three ; the body then consists 

 of thirty segments. Finally, in the adult state, the male has 

 thirty nine, and the female sixty-four; two years afterwards 

 they again experience a change, and then only do the genital 

 organs make their appearance. From the moment of their 

 birth, which occurs in March, until November, at which time 

 M. Savi terminated his observations, these changes take place 

 about once a month. In their exuviae, we find even the lining 

 membrane of the alimentary canal and tracheae. The organs 

 of the mouth were the only parts that Savi could not disco- 

 ver(l). 



These Insects feed on dead and decomposed animal and 

 vegetable matters ; they deposit in the ground a large number 

 of eggs. According to the system of Linnaeus they form but 

 one genus, that of 



luLUS, Lin. 



Which we divide as follows: 



Some have a crustdceous body without terminal appendages, and 

 antennae enlarged near the end. 



(1) See RuUet. Gener. et Univers. of the Baron Ferussac, Decemb., 1823. The 

 observations of Savi, an extract of which is contained in this work, were published 

 in a memoir, entitled " Osservazioni per servire alia storia di una specie di Julus 

 communissima," Bologna, 181". The same savant published another in 1819 on 

 the Jiilus fcatidissimus. 



Vol. III.— 2 G 



