454 AMPHISKENIDE. 
Monotrophis, Gray, Proc. Zool. Soc. 1865, p. 454. 
Dalophia, Gray, 1. c. 
Nostril pierced in a small nasal on the lower surface of the snout. 
Head depressed, with broad projecting snout, with cutting-edge. A 
strong gular fold. Pectoral segments enlarged. Preanal pores 
present or absent. Tail cylindrical, obtuse. 
Africa. 
Synopsis of the Species. 
I. A single large shield on the head. 
A. No preocular. 
42 to 48 segments in an annulus of 
the body; three lower labials .. 1. capensis, p. 455. 
82 or 34 segments in an annulus of 
the body ; two lower labials ...... 2. sphenorhynchus, p. 455, 
34 segments in an annulus of the body ; 
three lower labials ; no pranal 
POLES: tii chin ges) sat aia wet 3. welwitschii, p. 456. 
B. A preocular .............. 4, guentheri, p. 456. 
II. Two large shields on the head. 
A. Anterior head-shield not longer than the posterior; a pre- 
anal pore on each side. 
1. Two pairs of elongate pectoral shields. 
Nasals in contact with each other. .. 5. galeata, p. 457. 
Nasals separated by the rostral, which 
is longitudinally bisected ........ 6. dumerilir, p. 457. 
2. Three pairs of elongate pectoral shields. 
30 segments in an annulus of the body 7. scalper, p. 457. 
18 segments in an annulus ........ 8. magnipartita, p. 458. 
B. Anterior head-shields longer than the posterior ; no preanal 
pores. 
Pectoral shields large, elongate...... 9. anchicte, p. 458. 
Pectoral shields small, very numerous ; 
nO preocular .... ee eee ees 10. jugularis, p. 459. 
Pectoral shields small, very numerous ; 
BA PTBOlar sik ccseras viens das 11. koppenfelsii, p. 459, 
