COLEOPTERA, OR BEETLES.
| Fam. | Fam. | ||
| 1. Cicindelidæ | Tiger-beetles. | 4. Cetoniidæ | Rose-chafers. |
| 2. Carabidæ | Ground-beetles. | 5. Buprestidæ | Metallic Beetles. |
| 3. Lucanidæ | Stag-beetles. | 6. Longicornia | Long-horned Beetles. |
The above families comprise the extensive series of ground beetles (Carabidæ) containing about 9,000 species, and the Longicorns, which are nearly as numerous and surpass them in variety of form and colour as well as in beauty. The Cetoniidæ and Buprestidæ are among the largest and most brilliant of beetles; the Lucanidæ are pre-eminent for remarkable form, and the Cicindelidæ for elegance; and all the families are especial favourites with entomologists, so that the whole earth has been ransacked to procure fresh species.
Results deduced from a study of these will, therefore, fairly represent the phenomena of distribution of Coleoptera, and, as they are very varied in their habits, perhaps of insects in general.
MOLLUSCA.
The Mollusca are usually divided into five classes as follows:—
| I. | Cephalopoda | Cuttle-fish. |
| II. | Gasteropoda | Snails and aquatic Univalves. |
| III. | Pteropoda | Oceanic Snails. |
| IV. | Brachiopoda | Symmetrical Bivalves. |
| V. | Conchifera | Unsymmetrical Bivalves. |
The Gasteropoda and Conchifera alone contain land and freshwater forms, and to these we shall chiefly confine our illustrations of the geographical distribution of the Mollusca. The classification followed is that of Dr. Pfeiffer for the Operculata and Dr. Von Martens for the Helicidæ. The families chiefly referred to are:—
Class II.—GASTEROPODA.
Order 2.—Pulmonifera.