3(5 SYNOPSES AND DESCRIPTIONS. 



Hydrops lbacurus, pL Lf<j. 5. 



Coluber abacurus HoVbrook, L836, N. A. Hay. Uted., 1, \.19,pl. XXIII. 

 Hydrops abacurus Dum. & Bibr., L854, Erp. Gen., Tab. 65. 



Long, moderately stout, cylindrical; head very little larger than the 

 neck, depressed, rounded; tail short, thick, conical, one sixth tonne ninth 

 of the total. .Snout short, broad. Eye medium, over third and fourth 

 labials, pupil round. Mouth-cleft deep, slightly curved. Teeth little 

 larger backward. Head-shields eight. Internasals united. Prefrontals 

 reaching the orbit. Frontal hexangular. Nasal entire, grooved from the 

 nostril to the first labial. Nostril small, visible from above. Loreal 

 united with anteorbital. One anteorbital. Postorbitals two, lower small, 

 in a notch between the labials. Temporals 1+2. Labials seven, some- 

 times fused or divided, penultimate larger. Infralabials nine, fifth larger. 

 Submentals two pairs, hinder small. Scales smooth, glossy, rounded at 

 the end, in 19 rows, outer broader. Ventrals large, broad, 171 — 203. 

 Anal bifid. Subcaudals in 35 — 47 pairs. 



Ground color red, yellow in alcohol. Back and usually -top of head 

 bluish-black. The black color extends down the flanks in wedge-shaped 

 points, separated by wedges of the red, which sometimes extend to the 

 middle of the back. The bands of black extend nearly or quite to the 

 middle of the belly, where they meet or alternate with those from the 

 opposite side. Red occasionally encircling the neck or scattered over 

 the top of the head. Anterior labials and chin-shields, with rounded 

 spots of black. Largest specimen 54 inches long; tail 5f inches. Mis- 

 sissippi Valley and eastward, as far north as Illinois and Virginia. 



Hydrops quinquevittatus. 



Homalopsis quinquevittatus Ihim. S % Bibr., ls">4, Erp. Gin. VII, 975. 



Elongate, moderately stout, subcylindrical ; head distinct, little larger 

 than the neck, depressed, crown flat, muzzle narrow between the nostrils; 

 tail stout, tapering regularly to the point. Eye moderate, pupil round. 

 Mouth-cleft deep, outline curved. Posterior maxillary teeth longer, sepa- 

 rated by an interspace. Head-shields normal. Internasals small, narrow 

 in front. Frontal short, broad, truncate, or angled in front. Nasal divided 

 or entire. Loreal half as large as the anteorbital. Postorbitals two. Tem- 

 porals l-f2. Submentals two pairs, nearly equal, posterior diverging. 



