The brachiopods had two valved shells of very lovely shapes. They were a prophecy of the wonderful beauty that was to appear in the world. Some of the shells were only a quarter of an inch across, others were four inches, and a few varieties have been found with shells a foot wide. These were giants of their class. The outer surface of these shells was exquisitely chiselled, as a jeweller ornaments gold and silver plate, and the beauty of the shell was increased by brilliant colors. Red, green, yellow, blue-black, and rose-pink were the hues in which these pretty creatures disported themselves before the big staring eyes of the trilobites. Many of these animals moored themselves by peduncles to rocks or to other creatures, as barnacles do, and thus holding fast, they fished for their dinners with their fine net of filaments; for these delicate threads were not for locomotion, but were mouth appendages to catch something to satisfy the creature’s hunger. The brachiopods were, next to the trilobites, the most numerous and important group in the Cambrian age. But, while the trilobites died out with their age, some of the representatives of their pretty neighbors have existed ever since, and, no doubt, in the Silurian days they lived as contentedly among the corals, as they now live among coral groves in the South Pacific. Observation of a living animal of this class shows that having fastened itself by its peduncle to some firm holding place, it can very rapidly fold and unfold its finger-like filaments, creating around itself a little whirlpool, which inclines towards its mouth, and draws its food within reach. FOOTNOTES: [32] See Nature Reader, No. 1, Lessons 34-36. [33] Nature Reader, No. 2, Lesson 1. [34] Nature Reader, No. 2, Lesson 17. [35] Nature Reader, No. 2, Lesson 34. LESSON XVII. STONE FISH AND STONE LILIES. “The floor is sand like the mountain drift, And the pearl-shells spangle the flinty snow; From coral rocks the sea-plants lift Their boughs, where the tides and billows flow; The water is calm and still below, For the winds and waves are absent there, And the sands are bright as the stars that glow In the motionless fields of the upper air.” --PERCIVAL, _The Coral Grove_.