16 G. A. BOULENGER 



indicated in the adult, absent in the young. Posterior margin of 

 the carapace strongly serrated in the young , scarcely in the 

 adult. Middle vertebral shields much broader than long in the 

 young, longer than broad in the adult. Plastron yellow, bor- 

 dered with black. 



» That these specimens are correctly referred to the St. sinualus 

 of Smith and Peters, there can be no question. Whether we 

 are justified in separating St. sinuatus from St. nigricans appears 

 to me very doubtful now that I have been able to examine 

 more material. It is quite clear that the specific characters in 

 this genus are not properly understood, any more than the mode 

 of variation with age and sex. Thus we see that the vertebral 

 shields vary very much with age , being longer than broad in 

 fall-grown specimens of St. sinuatus. But in St. bottegi, which 

 may also have to be united with St. nigricans and sinuatus, 

 the second and third vertebral shields are much longer than 

 broad in a specimen 21 centimetres long, whilst they are only 

 as long as broad in my St. sinuatus of 22 centim. (See Cat. 

 Chelon., p. 194). 



5. Pelomedusa galeata , Schoepff. — Stagno Saha ; two half- 

 grown specimens. 



In one, the pectoral shields form a very short median suture ; 

 in the other, the left pectoral shield does not quite reach the 

 middle line. 



6. Trionyx triunguis, Forsk. — Lugh ; a single specimen. Ga- 

 nana; a skull. 



Laeertilia. 



7. Pristurus crucifer, Val. — Lugh and between Matagoi and 

 Lugh. Confluence of the Web and Ganana. 



Males with a very rudimentary caudal crest. Pupil sometimes 

 vertically subelliptical. 



8. Hemidactylus isolepis, Blgr. — Lugh; a single specimen. 



9. Hemidactylus frenatus, D. and B. — Brava ; numerous spe- 

 cimens. 



