FAMILIES OF LIZARDS. 649 
ORDER LACERTILIA. LIZARDS. 
Sauria, MivartT, MILNE EDWARDS. 
Body usually lacertiloid, in some species serpentiform ; feet usually four, sometimes 
two, and occasionally none; anal slit transverse ; bedy covered with scales, tubercles, 
or spines; top of head with plates; eyelids usually movable; teeth conical, not in 
sockets ; heart with auricles and a ventricle, the septum in the latter incomplete; 
urinary bladder present; vertebra procewlous except in the Geckos and Sphenodon where 
they are amphicolous ; sacrals separate, sometimes one, and never exceeding twe in num- 
ber; head of ribs simple, undivided ; sternum present except in the serpentiform species ; 
quadrate bone somewhat movable; rami of the lower maxillary usually firmly united ; 
alisphenoids and orbitosphenoids absent or rudimentary: parietal foramen usually dis- 
tinct; parotic processes long ; hyoid a median rod. 
The Lacertilia comprise a large order, with numerous species and families. Those 
inhabiting North America may be arranged as follows: 
* Bones of skull grown together; dorsal region covered with square plates; genera- 
tive organs simple; feet rudimentary or none. ¢ P : AMPHISBAENID/, 
* Bones of skull distinct; dorsal region usually scaly; penis and vagina bifid; feet 
usually well developed. a. 
a. Tongue flat, elongate and bifid. 06. 
a. Tongue thick, convex, attached at base to esophagus. c. 
db. Abdominal region covered with roundish scales, quincuncially arranged and 
resembling those of the back. d. 
b. Abdominal region covered with square plates. e. 
e. Dorsal scales granular; eyes large, almost without lids. . GHCKOTIDA. 
ce. Dorsal scales imbricated ; eyes moderate; lids distinct. . . IGUANIDE, 
d. Kyes and eyelids nearly or quite concealed. ff. 
d. Eyes and eyelids prominent. : ; : : ; : SCINCIDZ. 
e. Teethsolid; cephalic shields large. g. 
e. Teeth hollow or grooved behind. h. 
J. Head conical; rostral cup-shaped. dain ; . . TYPHLINIDZ. 
f. Head depressed ; rostral elongated. ¢ : : . TYPHLOPSIDZE. 
g. Sides flattened, without lateral fold. A. 
g. Longitudinal lateral fold or stripe present. 4. 
h. Cephalic shields small. : ; ; HELODERMIDZ, 
h. Cephalic shields large, regular. 1. 
i. Ear distinct. j. 
a 
Ear concealed. : : : : x : CHALCIDE. 
j. Limbs two or none; body serpentiform ; no femoral pores. ANGUIDZ. 
j. Limbs four; body more or less lacertiloid. . . . ZONURIDA. 
l. Supraorbital plate bony. : - : : : LACERTIDZ. 
l. Supraorbital plate horny. 4 “4 : TEIDA. 
Of these families, Amphisbaenidz has one genus Rhineura, with one species, floridana, 
inhabiting Florida; Geekotidw has four, Coleonyx, Sph@rodactylus, Phyllodactylus, and 
Diplodactylus, of which Spherodactylus notatus occurs in Florida, the remainder range 
from Texas to the Pacific coast ; Typhlinide has Aniella pulchra in California ; Typhlop- 
sidx, one genus, Stenostoma, with two species ranging from Texas to the Pacific; Teidx 
has Cnemidophorus and Verticaria; Helodermidxw has Heloderma horridwm in Mexico; 
