778 REPORT OF NATIONAL MUSEUM, 1898. 



can districts. They are snakes of fragile structure, inhabitants of 

 brush, with feeble dentition. The head has the appearance of that of 

 a foetal snake, with the sbort nose and large eye. They are said by 

 Dum(^ril and Bibrou to live on Mollusca. Their immense tracheal lung 

 distinguishes them from the Dromicinae, which they resemble in penial 

 characters. 



The hemipenis in LeptognatJms is not bifurcate, but the sulcus is 

 deeply so. It is oalyculate from the bifurcation of the sulcus to the 

 extremity, and the calyes are fringed. Below them the organ is fur- 

 nished with hooked spines halfway to the base. Below them the sur- 

 face is smooth. 



COLTJI? Rijsr^. 



This subfamily includes representatives of the Calamarinae, Coronel- 

 linoe, Lycondontinse, Colubrinse, and Dryadiuse of authors, and includes 

 burrowing, ground, and arboreal types. The group is especially char- 

 acteristic of Palearctica and Nearctica, but numerous forms occur also 

 in the Oriental, Ethiopian, and Neotroijical realms. There is a general 

 similarity in penial structure, the diversities being of minor importance 

 and some of them not yet fully understood. I have been able to abol- 

 ish the division Coronellinte, which never had any real standing, and 

 also to show that Hallowell was right when he referred the Lycodon 

 rufozonatus of authors to the neighborhood of Coronella. The genera 

 of burrowing habits and generally small size, which were variously 

 referred to the Calamarinae and Coronellinse, generally have the ruch- 

 ing of the hemipenis reduced and replaced by spines. This is consiiic- 

 uous in StyJaso7iia, and especially in Conopsis, where there is but one 

 row of calyces, and in AdelpJiicus and Trimetopon, where the cups are 

 replaced by unossifled papillae. 



In the typical species of Ophibolus the calyces are much reduced in 

 number and replaced by spines. Some genera have the borders of the 

 calyces conspicuously papillose, while in others they are smooth, but 

 intermediate conditions connect them. In some forms there are smooth 

 patches on the apex of the organ, but the value of this character is 

 uijcertain. In Cynophis I have found a remarkable apical awn, but as 

 I have had the opportunity of examining but one individual, I am not 

 sure how constant it is. In the Tropidoclonium Uneatum, where a simi- 

 lar character is present, I have found it to be entirely constant. 

 I give the following synopsis of the genera which I have been able to 

 examine : 



I. Hypapophyses not pierciug CBSophagus. 

 * Apical calyces of hemipenis present. 

 A. The calyces not furnished with spines, excepting the inferior marginal ones. 

 a No apical awn or papilla. 

 yS Not capitate. 



y Calyes very large, few, and shallow. 

 Isodont; colubriform ; anal divided Cacocalyx Cope.' 



' Type, Drymobiua percarinatus Cope ; Costa Rica. 



