142 ON THE BATRACHIA AND REPTILIA OF COSTA RICA. 



A loreal ; anal entire ; two nasals ; rostral produced. Cemophora, Cope. 



A loreal ; anal divided ; one nasal ; rostral much produced. Chionactis, Cope. 



A loreal; anal divided; two nasals, rostral obtuse, not produced. Sonora, B. & G. 



o. Subcaudal scutella entire. 

 Rostral produced ; scuta normal. Rkinochilus, B. & G. 



(3 j. Dentition glyphodont. 

 Rostral little produced ; nasal distinct, undivided. Ogmius, Cope. 



IV. Prefontals continuous on the middle line. 

 Internasals distinct; rostral produced. IAgonirostra, Cope. 



Internasals medially united. Prosymna, Gray. 



The preceding genera are all Mexican, Sonoran, or from adjoining regions, 

 excepting IAgonirostra and Prosymna (African). IAgonirostra, Cope (Amer. Journ. 

 Sci. Arts, 1863) was formerly called Temnorhynchus by Smith, but that name was 

 preoccupied. 



There are only two species of Stenorhina, but several subspecies, which differ 

 as follows : — 

 Eight inferior labials, fifth largest. No loreal ; narrow cross-bands. 



& kennicottiana, Cope. 

 Seven inferior labials, fourth largest. Seventeen rows scales ; temporals 1-2. 



S. degenhardtii, Berth. 

 Subspecies I. Adults plumbeous-brown ; no loreal ; young with broad cross- 

 bands. S>. d. ventralis, D. B. 

 Subsp. II. A loreal; scales above the third row with a black tip; ground color 

 pale brown. S. d. apiata, Cope. 

 Subsp. III. Loreal present or absent; five black longitudinal bands on a light 

 brownish ground. & d. freminviUei, D. & B. 

 The & d. apiata is from Tehuantepec, from Sumichrast. 



401. Tantilla melanocephala, Linn., Dum. Bibron, vii. p. 859. 

 From Van Patten's collection. 



separated from each other by scales. Scales of the bod}' smooth, poreless, and in fifteen longi- 

 tudinal rows. Gastrosteges 118; anal double; urosteges 25. 



Color very pale yellow, each scale, excepting those of the first row, with a brown apical spot, 

 which is in all except the two outer of these, continued to the base of the scale as a brown line. 

 Head above dark brown, with an oval yellowish ellipse surrounding the middle portions, passing 

 round the muzzle and superciliary, and through the length of the parietal plates as a wide baud. 

 Below unspotted. Total length in. 160; length to rictus oris, .005; of tail, .020. 



Found by Dr. Francis Sumichrast on the west side of the State of Tehuantepec, Mexico, and 

 sent by him to the Smithsonian Institution (No. 8). 



To the above description I add that the Toluca frontalis, Cope, from Colima, is congeneric 

 with this species in all technical characters. 



