1. Uncovered (Apertum). When it is not concealed by the shield of the prothorax.—Ex. Hymenoptera.

2. Covered (Tectum). When it is quite concealed by the prothorax.

3. Areate (Areatum). When it is larger than the prothorax, and terminates towards the wings in two oblique areas, inclosed by a ridge often crowned anteriorly with little teeth.—Ex. Libellulina. Plate [IX]. Fig. 7. g., a. N.B. The space between these areas is fitted with a membrane capable of tension and relaxation, which in flight causes them to approach to and recede from each other.

4. Amplectent (Amplectens). When posteriorly it is so curved as to form a large sinus which embraces the dorsolum.—Ex. Vespa L. Plate [IX]. Fig. 11. g..

5. Phonetic (Phoneticum). When its posterior angles, approaching the wings, cover the vocal spiracles[1103].—Ex. Hymenoptera.

β. dorsolum.

1. Thoraciform (Thoraciforme). When it forms the principal part of the upper surface of the trunk.—Ex. Bombus, Apis, Vespa &c. Plate [IX]. Fig. 11. i..

γ. scutellum.

1. Distinct (Distinctum). When it is separated from the dorsolum by a suture.—Ex. Hymenoptera, Diptera. Plate [IX]. Fig. 11, 19, &c. k´.

2. Coalite (Coalitum). When it is not separated from the dorsolum by a suture.—Ex. Coleoptera, &c. Plate [VIII]. Fig. 3. k´.

3. Scutellate (Insectum scutellatum). An insect having a visible scutellum.—Ex. Melolontha.

a. Rejected (Rejectum). When, though visible, it does not intervene between the elytra at their base.—Ex. Passalus.

b. Received (Receptum). When it intervenes between the elytra at their base.—Ex. Most scutellate Coleoptera.

4. Exscutellate (Insectum exscutellatum). When an insect has no visible scutellum, it being wholly covered by the Prothorax.—Ex. Copris.

5. Ascending (Ascendens). When it curves upwards from the dorsolum.—Ex. Sagra.

6. Tabular (Tabulare). When it is elevated on a footstalk above the dorsolum, and forms a tabular or flat surface.—Ex. Elater.

7. Obumbrant (Obumbrans). When it overhangs the metathorax.—Ex. Musca. Plate [IX]. Fig. 19. k´.

δ. base-covers (Tegulæ).

1. Conchiform (Conchiformes). When they are a semicircular concavo-convex scale something resembling the valve of a bivalve shell.—Ex. Hymenoptera. Plate [IX]. Fig. 11, 12. g´´.

2. Laciniform (Laciniformes). When they are long, of an irregular shape, and appear like lappets on each side of the trunk.—Ex. Lithosia, &c. Plate [IX]. Fig. 5.[1104]

ε. elytra.

1. Base (Basis). The part next the Prothorax.

2. Apex (Apex). The part next the Anus.

3. Humeral Angle (Angulus Humeralis). The exterior basal angle.

4. Scutellar Angle (Angulus Scutellaris). The interior basal angle.

5. Coleoptra (Coleoptra). The two elytra spoken of together.

6. Spinigerous (Spinigera). When the Coleoptra have a spine common to them both.—Ex. Cassida bidens.

7. Auriculate (Auriculata). When the Elytra have an elongate process at the shoulders.—Ex. Cassida bicornis, Taurus, &c.

8. Intire (Integra). When they have neither abbreviations nor incisions.

9. Fastigiate (Fastigiata). When of equal or greater length than the abdomen, and transverse at the end.

10. Truncate (Truncata). When they are shorter than the abdomen, and transverse at the end.

11. Abbreviate (Abbreviata). When they are shorter than the abdomen, but cover more than half its length. Plate [I]. Fig. 4.

12. Dimidiate (Dimidiata). When they are about half the length of the abdomen. Plate [I]. Fig. 5.

13. Very Short (Brevissima). When they are not half the length of the abdomen. Plate [I]. Fig. 2, 3, 7.

14. Mutilate (Mutilata). When they appear unnaturally short or curtailed as if mutilated.—Ex. Acrydium.

15. Subulate (Subulata). When they are attenuated towards the end.—Ex. Sitaris humeralis.

16. Elongate (Elongata). When they extend beyond the anus.—Ex. Trox.

17. Obvolving (Obvolventia). When their Epipleuræ cover a considerable portion of the sides of the alitrunk. Plate [XXVIII]. Fig. 7.

18. Complicant (Complicantia). When they lie a little over each other.—Ex. Meloe. Plate [I]. Fig. 6.

19. Dehiscent (Dehiscentia). When they diverge a little at the apex.—Ex. Pyrochroa.

20. Ampliate (Ampliata). When they are disproportionably wide at the end.—Ex. Lycus fasciatus. Plate [XIII]. Fig. 20.

21. Plicate (Plicata). When they have two or three contiguous abbreviated furrows which exhibit the appearance of folds.—Ex. Pselaphidæ.

22. Perforate (Perforata). When a little hole appears drilled through them.—Ex. Cassida perforata.

N.B. Many of the above terms will apply to Tegmina, Hemelytra, Wings, &c.