242 



REMARKS ON THE NATURAL ARRANGEMENT OP THE MYRIAPODA. 



Thus it will be seen that he elevates two of M. Brandt's families to the rank of tribes, and 

 unites his Sugentia and Trizonia to constitute a third. To show, perhaps, a little more 

 clearly and correctly the relations of these three arrangements, a table is appended, in 

 which the positions of the families, &c, are altered from the places originally assigned to 

 them by the authors, so as to compare with one another. 



C H ILOGNA T II A. 



Q ERVAIS. 



Fain. Polyxenidae. . 



Fam. Glomeridee. . 

 Fam. Polydesmidse. 

 Fam. Iulidac. . . . 

 None Fam. Polyzoniidso. 



Gray. 



Fam. Polyxenidae. . . 



Fam. Glomeridaa. "1 

 Fam. Zephroniids. J 



Fam. Polydesmidse. . 



Fam. Iulidae 



Fam. Craspodcsomidse. 



Brandt. 



Newport. 



. Fam. Monozonia (partim). . Tribe, Monozonia (partim). 



Fam. Polyxenidae. 

 . Fam. Pentazonia Tribe, Pcntazo-nia. 



Fam. Glomeridse. 

 . Fam. Monozonia (partim'). . Tribe, Monozonia. 



Fam. PolydesmidiB (partim). 

 . Fam. Trizonia Tribe, Bizonia ('partim), 



Fam. Iulidae (partim). 



. Order, Sugentia Tribe, Bizonia (partim). 



Sections, Ommatophora, Fam. Polyzoniidae. 



Typblogcna. Fam. Siphonophoridac. 



The characters employed by the several authorities in separating the various groups 

 are so different and often so defective as to make it a task of some difficulty to understand 

 the exact limits of their families, &c., and almost impossible to compare the several classi- 

 fications so as to produce a regular synonymy of the genera. In some cases characters have 

 been assigned as generic which vary not merely in the same species, but even in a single 

 individual. Mr. Brandt has given more fully than any of the others the sum of the differences 

 between his families ; but even he has not seized and brought forward, as seems to me at least, 

 the separating distinctive characters which run all through, so as to show the unity of the 

 plan of the creation of this ('lass ; or, in other words, the successive steps in the Divine 

 thought, which is embodied and,' as it were, crystallized into form. Although this mono- 

 graph of a single fauuic group is not the place for a discussion of the history of the classi- 

 fication of the Myriapoda, yet it lias seemed necessary to make this brief notice of and 

 comparison between the works of the more recent authorities, before introducing what 

 appears to the author to be the natural arrangement, which has been gradually deve- 

 loped by the various efforts ; each adding something, each pushing forward a little towards 

 the truth. 



As has been stated before, the arrangement of the Chilopoda adopted is precisely that 



