THE SIDE-NECKED TORTOISES 



2449 



tnatamata will occasionally eat vegetable substances, its chief food consists of fish, 

 frogs, and tadpoles, some of which may probably be attracted within reach by 

 mistaking the appendages on the neck for plants or animals on which they feed. 

 The matamata is, however, stated to capture some of its prey by swimming swiftly 

 among water plants, diving immediately when a fish or frog is seized in its beak. In 

 captivity this tortoise is sluggish, frequently dying after a few weeks through 

 refusal to feed. 



MATAMATA TORTOISE. 



(One-fifth natural size.) 



The snake-necked tortoises, of which there are two South-American 

 species {Hydromedusa maximiliani and tectifera], agree with the 

 matamata in their long necks and ( weak jaws, but differ in their 

 smooth shell, the absence of a proboscis to the nose, and the presence of only four 

 claws on each foot the matamata having five claws on the fore- feet and four on the 

 hinder pair. The flattened shell in the young state has an interrupted median 

 ridge, and presents the unique peculiarity that the broad nuchal shield of the cara- 

 pace is placed behind the first pair of marginals (which consequently meet in the 

 middle line), and thus simulates a sixth vertebral shield. The figured species (//". 

 tectifera), which ranges from Southern Brazil to Buenos Ayres, has a shell measur- 

 J 54 



