1879.] ^*** [Cope. 



28. Crotalus polystictus Cope. C. triseriatus Jan. nee. Wagler. C. 



ximenesii Duges. 



Remarks. 



Points of interest in geographical distribution, indicated by the collection 

 of Dr. Duges, are the following: The species of the above list which be- 

 long distinctively to the Sonoran district fauna are five, viz : Bufo punc- 

 tatus, Hyla arenicolor, Spea hammondi, Eutcenia cyriopsis, Hypsiglena 

 ochrorhynchus. Besides these genera, the following belong to the Nearctic 

 Realm, and not to the Neotropical : Rana, Sceloporus, Holbrookia, Phimo- 

 thyra, Bascanium. Cystignathus is the only Neotropical genus ; while 

 Mahtchylodes, Ogmius, Canopsis and Trimorphodon are especially Mexican. 



I add that Dr. Duges has sent Hypopachus variolosus Cope, from the 

 State of Guadalaxara, a species heretofore only known as Costa Rican. 



III. Tehuantepec, Sumichrast. 



A list of species from this locality and collector was published in the 



Proceedings American Philosophical Society for 1869, p. 161. Since that 



date a number of collections have been sent by Mr. Sumichrast, which add 



materially to our knowledge of the distribution of the Batraehia and Rep- 



tilia of the district of Mexico properly so called. I append Mr. Sumichrast's 



notes. 



Batkachia. 



1. (Edipus rufescens Cope, 10042 (15). Heretofore only known from 

 Vera Cruz. Found in tufts of Tillandsia. 



2. (Edipus carbonarius carbonarius Cope. 



2. (Edipus carbonarius salvini Gray. 



3. Siphonops mexicanus D. & B. 



4. Bufo agua Daud. 



5. Bufo sternosignatus Gthr., 10014 (No. 2). Only found in the begin- 

 ning of the rainy season breeding in pools. 



6. Bufo canaliferus Cope, 10015, 10022 (No. 3). Found in woods, and 

 not seen in pools at the breeding season. 



7. Bufo coccifer Cope. 



8. Bufo valliceps Wiegm., 10013 (No. 1). 



9. Microphryne pustulosa Cope, 10023-8. 



10. Engystoma ustum Cope, 10021. 



11. Rhinophrynus dorsalis D. & B. 



12. Hyla miotympanum Cope. 



13. Smilisca baudini D. & B., 10016 (No. 4). Abundant, but only seen 

 in the rainy season, when it comes to pools, lagoons, etc., to breed. 



14. Hylella platycephala, sp. nov. 



This species conforms to the characters of the genus Uylella, as I under- 

 stand them, viz: in the general structure of Hyla, including fronto-parietal 

 fontanelle and narrow divergent nasal bones, but wanting vomerine teeth. 



The present species is not large and has elongate hind limbs, the heel 

 reaching the middle of the orbit. The sole of the hinder foot is rather 



