Usa "tetrad" in una frase

1. Conseil, I also retrieve certain fish from the genus Tetradon unique to these seas: southern puffers with red backs and white chests distinguished by three lengthwise rows of filaments, and jugfish, seven inches long, decked out in the brightest colors

2. The coinage in circulation in Egypt, during the Achæmenidean supremacy was all of foreign origin, the staters of the Kings of Tyre and Sidon and the tetradrachmas of Athens