ST E liE( )aEN rs LI B YCA. 
30 :] 
the anterior and posterior costals respectively. The distance between the anterior 
neural and the nuchal is d'G cm., that between the last neural and the snprapygal 
1-9 cm. The anterior nenrals are much longer than wide, but the series shortens 
Text-fig. 97. 
^ ig Nu 
1 ' I 
Carapace and plastron of Stereogenys libyca : A, carapace ; B, plastron ; 0, shell from right side. 
Ent., entoplastral bone ; g., gular shield ; Hy.p., hyoplastral bone ; Ilyp.p., h ypoplastral bone ; ig., inter- 
gular shield; Ms.p., mesoplastral bone; n., humeral shield; Aa., michal bone ; peel., pectoral shield; 
Pyg-i pygal bone ; v. 1-5, vertebral shields ; Xi.p , xiphiplastral bone. 1 nat. size. 
(From the Ann. & Mag. Nat. Hist. [7] vol. xi.) 
from before backwards, so that the posterior ones are wider than long. 't'hey are 
hexagonal in outline, with the exception of the first and last, which are pentagonal. 
