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.
CHILOGNATHA.
| Gray. | Gervais. | Brandt. | Newport. | |
| Fam. Polyxenidæ | Fam. Polyxenidæ. . . . | Monozonia (partim). . | Tribe, Monozonia (partim). Fam. Polexnidæ | |
| Fam. Glomeridæ. Fam. Zephroniidæ. |
Fam. Glomeridæ. | Fam. Pentazonia | Tribe, Pentazonia. Fam. Glomeridæ. | |
| Fam. Polydesmidæ. | Fam. Polydesmidæ. | Fam. Monozonia (partim) | Tribe, Monozonia. Fam. Polydesmidæ (partim). | |
| Fam. Iulidæ Fam. Craspedesomidæ. |
Fam. Iulidæ | Fam Trizonia. | Tribe, Bizonia ( partim). Fam. Iulidæ (partim). | |
| None | Fam. Polyzoniidæ. | Order, Sugentia Sections, Ommatophora, Typhlogena |
Tribe, Bizonia (partim). Fam. Polyzoniidæ. Fam. Siphonophoridæ. | |
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 classifications 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 class; or, in other words, the successive steps in the Divine thought, which is embodied and, as it were, crystallized into form. Although this monograph of a single faunic group is not the place for a discussion of the history of the classification of the Myriapoda, yet it has 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 developed 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
