634 MR, G. A. BOULENGER ON THE 



3. Aparallactus CONCOLOR. 



Uriechis concolor Fischer, Jahrb. Harnb. Wiss. Anst. i. 1884, 

 p. 4, pi. i. 



Aparallactus concolor Bouleng. Oat. Sn. iii. p. 257. 



Uganda and Somaliland. 



4. Aparallactus lunulatus. 



Uriechis lunulatus Peters, Mon. Bei-l. Ac. 1854, p. 623, and 

 Reise Mossamb. iii. p. 113, pi. xviii. fig. 2. 

 Aparallactus lunulatus Bouleng. t. c. p. 258. 

 Lake Tanganyika, N'yassaland, Mozambique. 



5. Aparallactus christyi Bouleng. Ann. & Mag. N. H. (8) v. 

 1910, p. 512. 



Uganda. 



6. Aparallactus guentheri Bouleng. Ann. & Mag. N. H. (6) 

 xvi. 1895, p. 172, and t. c. p. 259. 



East and Central Africa, S. Rhodesia, Angola. 



7. Aparallactus capensis A. Smith, 111. Zool. S. Afr., Rapt. 

 App. p. 16 ; Bouleng. Oat. Sn. iii. p. 259. 



East and South Africa, Katanga. 



8. Aparallactus nigriceps. 



Lhiechis nigriceps Peters, Mon. Berl. Ac. 1854, p. 623, and 

 Reise Mossamb. iii. p. Ill, pi. xviii. fig. 1. 

 Aparallactus nigriceps Bouleng. t. c. p. 260. 

 Mozambique and Nyassaland. 



9. Aparallactus punctatolineatus Bouleng. Ann. & Mag. 

 N. H. (6) xvi. 1895, p. 173, and Cat. Sn. iii. p. 261. 



Nyassaland, Angola. 



C. Proteroglypha. 



(Loreal absent in all the genera.) 



I. Tail compressed ; no distinct veutrals (Marine) Si/drus. 



II. Tail not compressed ; ventrals large. 



A. Head short; snout broader than long; bod}' cj-lindrical ; snbcaudals less 



than 80. 



Scales not at all oblique; ventrals 192-193 ; subcaudals 67-78 Boidengerina, 



Scales more or less oblique, sometimes very slightly ; ventrals 141- 



172; subcaudals 13-25 Elapechis. 



Scales oblique ; ventrals 180-228 ; subcaudals 50-72 Naia, 



B. Head long, narrow ; snout not broader than long ; bodj' 



slightly compressed ; scales very oblique ; ventrals 202- 



270; subcaudals 97-121 Den<Jmspig. 



