Fig. 139. Tellina virgata (Linnæus).
Next to Donax naturalists rank the genus Tellina, which includes many species of very minute shells, all remarkable for their beauty of form, and for their brilliant and varied colours. One of these, called the Rising Sun (Tellina radiata), is represented in Fig. 138. The Tellinas are found in every sea; the French coast furnishes many species: examples, Tellina virgata (Fig. 139) and Tellina sulphurea (Lamarck) (Fig. 140). In Fig. 141 Tellina donacina is represented with its two vital tubes, or syphons.
Fig. 140. Tellina sulphurea (Lamarck).
Fig. 141. Tellina donacina (Linnæus).
The seventh family, or Mactridæ, include Lutraria and Mactra, or the otter and kneading-trough shells. They are widely distributed; there are several British species of both.
The eighth family, Veneridæ, includes Venus, Cytherea, Meroe, and Artemis; beautiful genera, and as such called by Linnæus and his followers after heroines of Greek mythology. Petricola, Venerupis, Tapes, Lucinopsis, and Trigona, also belong to the family. These acephalæ of size so small, like their congeners, inhabit every sea; they are found in every region of the globe, more than a hundred and fifty species being known. The shell is elliptic in form, the valves smooth, striated, spiny, and lamellous, like those of Cardium and Donax. Like these, they bury themselves in the sand.
Fig. 142. Venus verrucosa (Linnæus).