1. Eleutherata[1411]. (Coleoptera L.) Maxilla naked, free, palpigerous.
2. Ulonata[1412]. (Orthoptera Oliv.) Maxilla covered by an obtuse galea or lobe.
3. Synistata[1413]. (Neuroptera L., excluding the Libellulina, and taking in Termes L. and Thysanura Latr.) Maxilla geniculate at the base and connate with the labium.
4. Piezata[1414]. (Hymenoptera L.) Maxilla corneous, compressed, often elongate.
5. Odonata[1415]. (Libellulina McL.) Maxilla corneous, toothed, two palpi.
6. Mitosata[1416]. (Myriapoda Leach.) Maxilla corneous, vaulted, not palpigerous.
**
7. Unogata[1417]. (Pulmonary Arachnida Latr.) Maxilla corneous, armed with a claw.
***
8. Polygonata[1418]. (Isopod and Branchiopod Crustacea Latr.) Palpi mostly six; Maxillæ many within the labium.
9. Kleistognatha[1419]. (Brachyurous Decapod Crustacea Latr.) Many Maxillæ without the labium, closing the mouth.
10. Exochnata[1420]. (Macrurous Decapod Crustacea Latr.) Maxillæ many without the labium, covered by palpi.
****
11. Glossata[1421]. (Lepidoptera L.) Mouth with a spiral tongue between reflexed palpi.
12. Ryngota[1422]. (Hemiptera Latr.) Mouth with a rostrum, having a jointed sheath.
13. Antliata[1423]. (Diptera L., Anoplura Leach., Trachean Arachnida Latr. &c.) Mouth with a haustellum without joints.
The Orders of Fabricius are equivalent usually to the primary groups of the Linnean Orders, and are regulated chiefly by the antennæ.
In estimating the value of the above system, we must bear in mind that, according to the statement of its author, it was intended to be partly artificial and partly natural: artificial as to its Classes and Orders; natural as to its genera, species, and varieties[1424]. He admitted, however, that natural Classes, &c. do exist; but he contended that artificial ones should be substituted for them, till further discoveries had cleared the way for their satisfactory development[1425]. As therefore his system, in its primary and secondary groups, was confessedly artificial, and the only use of an artificial system being to facilitate the study of any department of Natural History, its value must be estimated by the facilities it affords to the entomological student. But here, it must be allowed, that instead of enlarging the entrance to the temple of his science, it has made it narrower, and has placed most discouraging impediments in his way.