137 



Family. CHALCIDA. 



CHARACTERS. 



1. The head is rather small, and is covered with polygonal plates. 



2. The teeth are not implanted in the maxillary bones, but are applied to their 



inner surface. 



3. The tongue is broad, free, notched in front, covered with squamiform or 



filiform papiUaB, and though slightly extensible, is not retractile in a sheath. 



4. The body is generally cylindrical, elongated or serpentiform, and has most 



commonly a deep groove along the flanks, produced by a fold of the skin. 



5. The body and tail are covered with verticillated plates or scales. 



6. The extremities are but slightly developed, or are entirely wanting. 

 Only one genus of this family is found in the United States — Ophisaurus. 



Vol. II.— 18 



