emydidæ

pl. [Lat. emys, gen it. emyd ( is ), and fem. pl. adj. suff. - idæ.] 1. Zool .: Terrapins, Mud Tortoises. A family of Chelonians. Feet palmated; claws five, four of them sharp; jaws horny; shell solid, covered with horny plates; marginal plates twenty-three or twenty-five, hinder pair free; sternal shields eleven or twelve; neck retractile. They are common in warm climates, but species exist in the temperate regions of both hemispheres. They are generally of small size. 2. Palæont.: The family has existed from Oolitic times till now. ěm-y-din, 8. [Gr. emys (gen it. emydos)=a turtle; suff. -in ( Chem.).] Chem.: A white nitrogenous substance contained in the yolk of turtles' eggs. It is soluble in dilute potash, swells up in acetic acid without di olving, and di olves in boiling hydrochloric acid without violet coloration. ( Watts : Dict. Chem.)