GLOSSARY. 395 



WHORL. The spiral turn of a univalve shell. 



XIPHOSURA (Gr. xiphos, a sword ; and oura, tail). An order of Crustacea, 

 comprising the Limuli or King-Crabs, characterised by their long sword- 

 like tails. , 



XvLOBirs (Gr. xulon, wood; bios, life). An extinct genus ot Myriapods, 

 named in allusion to the fact that the animal lived on decaying wood. 



ZAPHRENTIS (proper name). A genus of Rugose Corals. 



ZEUGI.ODONTIDJE (Gr. zevgle, a yoke; odous, a tooth). An extinct family of 



Cetaceans, in which the moiar teeth are two-fanged, and look as if composed 



of two parts united by a neck. 

 ZOOPHYTE (Gr. zoon, animal ; phuton, plant). Loosely aj ^ 



like animals, such as Sponges, Corals, Sea-anemones, Sea-mats, &c. 



