EXPLANATION OF PLATE V. 
MANDIBLES OF INDIAN SPECIES OF Trionyx. 
Figs. 1, 3, 4, 5 reduced; Ia, 2, 6 natural size. 
Fic. I, Ia, 2.—Trionyx gangeticus. 
I, ta. Old and young individuals from the R. Ganges ; 
2. Young individual from the R. Mahanaddi. 
Fic. 3.—Adult of T. hurum from the Gangetic delta. 
Fic. 4.—Adult of T. phayret from Arrakan. 
Fic. 5.—Adult of T. migricans from Chittagong. 
Fic. 6.—Half-grown individual of T. formosus from Burma. 
(The small projections at the tip of the jaw represented in 
fig. I are artificial. | 
