Cope.] IvZ I^Dec. 19, 



only differs from Rliadinsea in its diacranterian dentition ; a character 

 wliicli will probably prove to be not entirely constant. 



The present species is quite nearly allied to the A. undulatus of Wied. 

 The scales are in seventeen rows, and those of the first row are longer than 

 deep. The rostral plate is transverse, and its apex visible from above. The 

 internasal and prefrontal pair are wider than long. The frontal is elong- 

 ate and with parallel sides, and its length exceeds that of the muzzle in 

 front of it, and equals that of the common occipital suture. The occipital 

 plates are long, equaling the width between the posterior exterior angles 

 of the superciliary plates. The loreal plate is higher than long. The 

 single preocular reaches the summit of the front, but not the frontal plate. 

 Two postoculars, each deeper than wide. Temporals 1-2-3. Superior 

 labials eight, eye resting on fourth and fifth ; all longer than high, ex- 

 cepting the fifth. Inferior labials eight, fifth largest and in contact with 

 postgeneials ; all longer than deep. Postgeneials considerably longer 

 than pregeneials. Total length, .805 ; length of head to rictus oris, .021 ; 

 length of tail, .245. Gastrosteges, 150 ; urosteges, 88 ; anal divided. 



Color above bluish olive, with a median dorsal brown band with ill- 

 defined borders, of four scales in width. Sides, up to the front row of 

 scales inclusive, dark slate blue, which forms a band from the canthus 

 oris to the end of the tail, which extends also on the ends of the gastro- 

 steges and urosteges. On the anterior third of the length in the larger 

 specimen, and on the greater part of the body in the smaller, this part 

 of the band isolates itself into dark round spots ; on the upper edge of the 

 lateral band every other scale has a pale spot in the centre. Head dark 

 brown above. A black band passes through each eye from the end of the 

 muzzle, and following the edge of the occipitals unites on the nape into a 

 single median band which continues as the dorsal band. Belly yellow, 

 gastrosteges bluish at the bases and edges, forming cross-lines. 



Tachymenis hypoconia Cope. Proceeds. Academy Phila., 1860, p. 247. 

 Mesotes ohtrusus Jan., Archiv. p. la Zoologia Modena, 1863, Coro- 

 nellida3, p. 96. Abundant. 



Thamnodynastes nattereri Mikan. Abundant. 

 Drymobius pantherinus Merrem. 

 Herpetodryas carinatus Linn. 

 Philodryas schottii Fitz. Abundant. 

 Philodryas olfersii Licht. Abundant. 



Tropidodryas ^stivus D. &. B. Dryopliylax D. «fc B. ; Philodryas 

 Giinther. 



The name Tropidodryas is proposed for a genus which difi"ers from 

 Philodryas only in having keeled scales. It includes the T. cesiivus and 

 the T. serra {Dryophylax D. & B.). 



