The only known species is the Halicore Dugong. These animals live in societies, in shallow bays near the mouths of rivers, and in narrow arms of the sea where the depth is only two or three fathoms. In such situations they find abundance of sea-weed, which seems to constitute their only nutriment, and which they tear from the rocks by means of their flexible but powerful and fleshy lips. In the Sunda Isles Dugongs were formerly numerous, but their flesh is esteemed a dainty, and the species is now becoming scarce. The chase after them is carried on during very calm weather, and generally by night. Their vicinity is detected by the noise they make in breathing as they lie at the top of the water, when by approaching them cautiously in a boat, they are easily harpooned. When once the weapon is fixed, all the efforts of the assailants are directed to getting a rope round the tail of their victim, and this being accomplished it is quite helpless. The mother and her young, and also the male and his mate, show great attachment for each other; if one is caught, the capture of the other is a certainty, as the survivor, totally regardless of danger, gives itself up to its enemies. Birds. [Illustration: STONE EAGLE GUARDING HIS BOOTY.] IN the study of our beautiful and interesting friends, the Birds, it is useless to enter into any prolonged discussion concerning their structure and their habits in this limited space; we are too eager to arrange them in their proper families, and learn of the interesting traits of individuals. [Illustration: TAILOR BIRD.] There is one thing worthy of consideration, however, in studying the Birds as a whole, before taking up individuals; and that is their wonderful intelligence in the building of their nests and the care of their young. It is difficult to understand this intelligence as exhibited in Birds. In the Mammals, whose organization approaches nearer to our own, we are enabled partly to comprehend their joys and griefs, but in the case of Birds it is difficult to understand their sensations. To explain this mystery a word has been invented which proves generally satisfactory. Thus we call the sentiment which leads the Birds to perform so many admirable actions, instinct. The tenderness of the mother for her young for instance—a tenderness so full of delicacy and foresight, is, we say, only the result of instinct. It is agreed, however, that this instinct singularly resembles the intelligence called reason. Take the intelligence that is shown in the majority of Birds in the nest building. The Tailor bird—an East Indian Bird related to the Warblers—shows rare intelligence in constructing its nest by stitching together the leaves of plants; and as we study the individuals of the different families of Birds we will find numerous instances of this marvellous quality commonly known as instinct.