SYNOPSES AND DESCRIPTIONS. 61 
convex, bent backward. Nasal in two parts. Loreal trapezoidal. One 
anteocular. Postoculars two, subequal. Labials seven (7—8), gradually 
increasing in height backward to the penultimate, third and fourth in 
orbit (3d to 5th). Infralabials eight. Submentals two pairs, subequal, 
posterior diverging. Scales smooth, in 19 rows. Ventrals 159—169. 
Anal divided. Subcaudals 62—70 pairs. 
Gray above, white below. A band of brown from the forehead to the 
tail. A brown line from each nostril along the side of the head and mid- 
dle of the flanks, black-edged and becoming black backward. Labials 
and infralabials marked with brown. Sometimes a brown or black line 
near the edge of the abdomen. The dark edges of the subcaudals form 
a line under the middle of the tail. 
TACHYMENIS IMPERIALIS. 
Tarnroputs Inrertauis Baird (Kenn.), 1859, U. S. and Mex. Boundary Survey Rept., 23, pl. XIX, eel. 
Form tapering anteriorly and posteriorly; tail continuous with the body; 
head distinct from the neck; snout rounded. Rostral gibbous, twice as 
broad as high. Loreal as high as Jong. Internasals one third as large 
as prefrontals, larger than the loreal. Frontal elongate, narrow, pent- 
agonal, scarcely wider anteriorly. Anteocular one, large, wider above. 
Postoculars two, small, upper largest. Scales smooth, in 19 rows, central 
narrow and acute, outer broader. 
Deep purplish black above, with two dorsal stripes of yellowish-brown 
from head to tip of tail, and separated by a narrow vertebral line of the 
ground color. Head black above, with two narrow yellow lines from the 
nostrils to the sides of the occiput, crossing the upper angle of the orbit. 
Labials and under part of head yellowish, minutely mottled with black. 
Ground color of the back extending on to the ends of the ventrals. Mid- 
dle of the abdomen uniform light yellowish in the alcoholic specimen, said 
to be bright red in life. (From deser.) Brownsville, Texas. 
TACHYMENIS LATERITIA. 
CoNIOPHANES LATERITIUS Cope, 1861, Pr. Ac. N. Sc., Phil., 524. 
Head broad, pointed. Muzzle prominent, acute. Loreal square. Ocu- 
lars 1—2. Labials seven, eye over third and fourth, fifth very large. 
Infralabials ten. Scales in 19 rows. Frontal nearly as broad as long. 
Anal bifid. Total length 24 inches; tail 7 inches, 
