GLOSSARY. 415 



UNGULATA (Lat. ungula, hoof). The order of Mammals com- 

 prising the Hoofed Quadrupeds. 



UNGULATE. Furnished with expanded nails constituting hoofs. 



UNILOCULAR (Lat. unus, one; and loculus, a little purse. Possess- 

 ing a single cavity or chamber. Applied to the shells of Fora- 

 minifera and Mollusca. 



UNIVALVE (Lat. unus, one; valva, folding-doors). A shell com- 

 posed of a single piece or valve. 



URODELA (Gr. oura, tail; delos, visible). The order of the Tailed 

 Amphibians (Newts, etc.). 



VENTRAL (Lat. venter, the stomach). Relating to the inferior 

 surface of the body. 



VENTRICULITES (Lat. ventriculum, a little stomach). A genus 

 of siliceous Sponges. 



VERMIFORM (Lat. vermis, worm; and forma, form). Worm-like. 



VERTEBRA (Lat. verto, I turn). One of the bony segments of the 

 vertebral column or backbone. 



VERTEBRATA (Lat. vertebra, a bone of the back, from verier e, to 

 turn.) The division of the Animal Kingdom roughly character- 

 ized by the possession of a backbone. 



VESICLE (Lat. vesica, a bladder). A little sac or cyst. 



w 



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, characterized 



by their long sword-like tails. 

 XYLOBIUS (Gr. xulon, wood; bios, life). An extinct genus of 



Myriapods, named in allusion to the fact that the animals lived 



on decaying wood. 



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

 ZEUGLODONTID/E (Gr. zeuglf, a yolk; odous, a tooth). An extinct 



family of Cetaceans, in which the molar teeth are two-fanged, 



and look as if composed of two parts united by a neck. 

 ZOOPHYTE (Gr. zo'on, animal; phuton, plant). Loosely applied 



to many plant-like animals, such as Sponges, Corals, Sea- 



an-emones, Sea-mats, etc.). 



