SNAKES. 183 



1. DlPSADOBOA MACULATA. 



Eight upper labials, fourth and fifth coming into the orbit ; 

 ground colour? with small quadrangular black spots. 



«. Central America. From M. Parzudaki's Collection. 



Description of the specimen. — Habit like Dipsadomorphus tri- 

 goaatus. Body slender, compressed; tail elongate, tapering ; head 

 depressed, with fiat crown, broad behind, very distinct from neck ; 

 snout of moderate length, obtuse in front ; eye moderate, pupil 

 elliptic, erect. Rostral broad, obtuse and rounded above, reaching 

 the surface of snout ; anterior frontals small, square ; posterior ones 

 much larger, subquadrangular, slightly bent on the sides ; vertical 

 large, very broad in front, reaching the anterior ocular, with rather 

 convergent outer edges and a posterior right angle; occipitals 

 moderate, tapering, rounded, and not forked behind; three 

 posterior oculars ; anterior raised above the surface of crown ; 

 superciliary moderate ; one elongate loreal, tv\o nasals, nostril 

 between ; eight low upper labials, fourth and fifth coming into 

 the orbit ; ten temporal shields, two of which are in contact with 

 oculars. Scales smooth, in nineteen rows, those of the medial 

 row rather larger, and some regularly six-sided, the others of the 

 back nearlv square, those of the side rhomboidal ; ventral plates 

 obscurely keeled ; anal bifid ; subcaudals entire. Posterior max- 

 illary tooth longest, grooved ; anterior ones and palatine teeth 

 appear to be equal in length ; anterior mandibular teeth rather 

 longer. Our specimen, being discoloured, exhibits a uniform 

 dull yellowish coloration, some scales of the back and sides being 

 black. Length of cleft of mouth §" ; length of tail 7" ; total 

 length 28". 



2. DlPSADOBOA UNICOLOR. 



Nine upper labials, fourth, fifth and sixth forming the lower 

 edge of eye ; above uniform olive (in spirits) ; beneath uniform 

 yellowish. 



a. West Africa. From Mr. Rich's Collection. 



Description of the specimen. — Body and tail not much elongate, 

 much compressed ; head depressed, with flat crown, broad, veiy 

 distinct from neck, with short, obtuse muzzle ; eye moderate, 

 pupil elliptical, erect. Rostral as broad as high, just reaching 

 the surface of snout ; anterior frontals short, rounded in front, 

 posterior ones moderate ; vertical broad, reaching the anterior 

 ocular, with convergent outer edges and a right angle behind ; 

 occipitals moderate ; superciliary rather pointed in front, very 

 broad and rounded behind ; two posterior oculars, one high an- 



