5. @EOCALAMUS—6. MONOPELTIS. 453 
5. GEOCALAMUS. 
Geocalamus, Giinth. Ann. § Mag. N. H. (5) vi. 1880, p. 234. 
Head slightly compressed, snout rounded; rostral large; nasals 
small, lateral. Pectoral segments slightly enlarged, forming angular 
series. ‘Tail cylindrical, obtuse. A lateralline; agularfold. Pree- 
anal pores. 
East Africa. 
1. Geocalamus modestus. (Prats XXIII. fig. 5.) 
Geocalamus modestus, Giinth. 1. c..fig 
Amphisbena modesta, Strauch, Mél. Biol. Ac. St. Petersb. xi. p. 412. 
Premaxillary teeth 3; maxillaries 3—3; mandibulars 7—7. 
A strong circular fold separates the head from the body. Rostral 
forming an angle posteriorly, wedged in between a pair of large 
prefrontals, forming a short suture ; a square median frontal, in one 
specimen partly united with the prefrontals; a pair of frontals ; 
nasal small, smaller than the ocular; eye slightly distinct; three 
upper labials, first very small, three temporals, superior largest; 
mental trapezoid, followed by a rather smaller heptagonal chin- 
shield ; three lower labials, first smallest; a lateral chin-shield. 
Two hundred and thirty-eight to two hundred and forty-one annuli 
on the body, and twenty-nine on the tail; an annulus on the 
middle of the body consists of thirty-four to thirty-cight seg- 
ments, of which sixteen or eighteen are above, and eighteen or 
twenty below the lateral line; all the segments longer than broad, 
the median ventrals, however, nearly equilateral. The pectoral 
segments only feebly differentiated from the others, more elongate, 
forming angular series, pointing forwards. A distinct lateral 
line. Six anal segments, median pair largest. Four preeanal pores. 
Dorsal and lateral segments brown; the interspaces between them, 
as well as the lower surfaces, whitish. 
millim. 
Length to vent .............000 0. 205 
Pail’: asincidt wa duis ea ee alee gations 32 
Diameter of body ................ 55 
East Africa. 
a-c. Ad. Mpwapwa, 200 miles inland of H. W. Bates, Esq. [C.]. 
the coast opposite Zanzibar. (Types. ) 
6. MONOPELTIS *. 
Monopeltis, Smith, Ill. Zool. S. Afr., Rept. 
Phractogonus, Hallow. Proc, Ac. Philad. 1852, p. 62. 
* The number of rings on the dorsal and ventral series do not correspond. 
as in most other Amphisbeenians, not only on account of the pectoral shields, 
but also because very frequently the anterior ventral rings are larger than the 
dorsals. I have therefore constantly counted the annuli above the lateral line, 
commencing from the head. 
