200 THE CLASSIFICATION OF THE OPHIDIA. 



includes the large isodont ground snakes and their allies, a very few of which (Zam- 

 enis sj).) are diacranterian. The types with furcate sulcus with ruches or disc are 

 nearly always diacranterian in dentition. The JSatricine hemipenis is always asso- 

 ciated with continued vertebral hypapophyses. The smooth or plicate hemipenis is 

 very seldom associated with such hypapophyses. 



I repeat here in the main the groups indicated in my prodromus of 1893, with 

 the omission of the glyphodont genera. As I have not had access to some of the 

 Oriental and African genera, it may be necessary to introduce some changes into 

 some of the groups which include them. 



I. Hypapophyses restricted to the anterior part of the vertebral column. 

 a. No tracheal lung. 



Hemipenis spineless, smooth, plicate or papillose only Calamarinm. 



Hemipenis with apical disc ; no calyces ; spinous ; sulcus furcate Xenodontinm. 



Hemipenis calyculate, spinous ; sulcus furcate ; no disc DrpmiciiKB. 



Hemipenis calyculate, spinous ; sulcus simple ; no disc Oolubrince. 



aa. A tracheal lung. 

 Hemipenis as in Dromicinse Lepiognatldna. 



II. Hypapophyses present to the caudal region. Hemipenis without calyces. 



Hemipenis smooth, not spinous Anoplopliallina. 



Hemipenis spinous, without enlarged basal hook Lycodontince. 



Hemipenis minutely spinous, with enlarged basal hook or hooks Nairicinw. 



CALAMAKINiE. 



The genera of this group are of various external form and the hemipenis presents 

 considerable variety of structure. 



I. Fusiform. 



Hemipenis smooth, simple ; sulcus furcate * Calamaria Boie. 



Hemipenis transversely plicate ; sulcus simple ; extremity with two papilla? jOligodon Boie. 



Hemipenis smooth or nearly so ; apex membranous ; sulcus simple % Holarchus Cope. 



Hemipenis similar to Holarchus, but sulcus furcate § Dicraulax Cope. 



II. Colubriform. 



Hemipenis single, apex papillose Orayia Gthr. 



HI. Dipsadiform. 

 Hemipenis bifurcate, with papillae at the middle, and smooth apex || Pareas. 



It is probable that several genera allied to Calamaria resemble it in characters, 

 and that Simotes D. and B. belongs near to Holarchus. From their general resem- 

 blance it is also probable that Anoplodipsas Pet. and Amblycephalus Kuhl belong 

 near to Pareas. The subfamily is entirely Oriental, except Grayia, which is African. 



* Species examined : C. gervaisii. \ 0. subquadratus. \ II. ancorus, H. dolleyanus. 



%D. purpurascens triuotalvs. || P. moellendorjjii Boettg. 



