ox THE SHAKES OF WEST AFEICA. 267 



16. A List of the Snakes of West Africa, from Mauritania 

 to the French C-ongo. By G. A, Boulenger, F.B.S., 

 F.Z.S. 



[Received May 20, 1919 : Read June 17, 1919.] 



(Published Ly ppvniissioii of tlie Trustees of tlie British Museum.) 



(Text-figure.s 1 & 2.) 



After an interruption of four j'ears, clue to the restrictions 

 imposed on the Society's publications, I am now able to continue 

 the series of lists of African Snakes, accompanied by ni'tificial 

 keys and arranged according to districts, with tlie oliject of 

 facilitating identifications *. 



The present instalment deals witli tlie western pai'ts of Africa, 

 from Mauritania to tlie Fi'ench Congo inclusive! 3'. This division 

 is as artificial as the keys, for we know a great many Snakes, 

 until lately believed to be characteristic of West Africn. to 

 extend across the great forest region as far as Uganda and the 

 north-west of Lake Tanganyika. But it is convenient for 

 practical purposes, especially if this list be used in conjunction 

 with that dealing with the Belgian Congo, to which, liowevpr, 

 many additions have lieen made since its publication f. Our 

 knowledge of the Snakes of the interior of Africa is still so im- 

 perfect that attempts at mapping out the distiibution must be 

 I'egarded as very provisional. 



The figures, in lieu of a glossarj^, which have already appeared 

 in the ' Proceedings," are hei'e reproduced (text-figs. 1 S: 2). 



Si/nopsis of the Families. 



I. Worm-like, with small inferior mouth, eyes hidden or visible under the head 



sliields, and body covered with uniform imbricate scales above and Ijeneatli. 



Ocular shield not l)ordering tlie mouth ; tail not or but little 



longer than broad ; 18 scales of more round middle of body ... Trrnr.oriD.T). 



Ocular shield bordering the mouth ; 14 scales round middle 



of body Glauconiip.t: 



II. Mouth large, eyes distinct, exposed ; body with enlarged shields beneath. 



Ventral shields much narrower than the body ; supraocular, if 



distinct, broken up into two or more shields RoiD.?;. 



Ventral shields at least nearly as In'oad as the body ; supraocular 

 single; poison-fangs, if b(dow the eye, preceded by smaller 

 teeth ColubkiP-t:. 



^'entral shields nearly as broad as the body ; large poison-fangs 



in a very large sheath below the eye ^'IPERIP.l^ 



Family T Y P 11 L o P i D .E. 

 A single genus. 



1. Typhlops. 



Schneid. Hist. Amph. ii. p. 339 ; Bouleng. Cat. Sn. i. p. 7 



* P. Z. S. 1915, pp. 193, 369, 611, 641. 



t Cf. Boulenger, Ann, Zool. Afr, vii. 1919, p. 1. 



