EXPLANATION OF PLATE II. 
Fig. I. — Trygon uarnak var. variegatus (adult female). Scale about -jL- 
,, la. — Trygon uarnak (young). Scale 
,, 2. — Trygon gerrardii (adult female). Scale | . 
,, 3. — Denticles on upper surface of tail of Trygon microps (nat. size). 
M 3 ^- — Denticles on centre of back of same species, x 2. 
,, 4. — ^Head of Myliohatis nieuhofii var. cornifera (nat. size). 
4«. — Denticles on back of same species, much enlarged. 
