O. GEOCALAMUS — 6. MONOPELTIS, 453 



5. GEOCALAMUS. 



Geocalamus, Giinth. Ann. i^- 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 lateral line ; a gular fold. Prae- 

 anal pores. 



East Africa. 



1. Geocalamxts modestus. (Plate XXIII. fig. 5.) 



Geocalamus modestus, Giinth. I. c. fig. 



Amphisbitua mode,sta, StrmicJi, Mel. Biol. Ac. St. Petersh. xi. p. 412. 



Proemaxillary 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 

 prsefrontals, forming a short suture ; a square median frontal, in one 

 specimen partly united with the pra^froutals ; a pair of frontals ; 

 nasal small, smaller than the ocular ; eye slightly distinct; thi'ee 

 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 ou the 

 middle of the body consists of thirty-four to thirty-eiglit 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 vcntrals, 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 prgeanal pores. 

 Dorsal and lateral segments brown ; the interspaces between them, 

 as well as the lower surfaces, whitish. 



millim. 



Length to vent 205 



Tail 32 



Diameter of body 5-5 



East Africa. 



a-c. Ad. Mpwapwa, 200 miles inland of H. W. Bates, Esq. [C]. 



the coast opposite Zanzibar. (Types.) 



(). MONOPELTIS*. 



Monopeltis, Smith, 111. Zool. S. Afr., Kept. 

 Phractogonus, Hallow. Proc. Ac. PhUad. 1852, p. G2. 



* The number of rings un Llie dorsal and ventral series do not correspond, 

 as in most other Anipliisbseiiians, not only on aocount of the pectoral shields, 

 but also because very treqiienlly tlio anterior venlral rings are larger than the 

 dorsals. I have therefore cnustuntlj' counted the annuli above tlie lateral line 

 commencing from the head. 



