THE DUCK-BILL, OR MULLINGONG. 637 



slightly variegated by differently tinted hairs, and the head and face being darker than the body 

 and limbs. The hair has a curious, hay-like aspect, being coarse, flat, and harsh towards the 

 extremity, although it is very fine towards the root. Owing to the color and structure of the 

 hair, the Ai can hardly be distinguished from the bough under which it hangs, and owes much 

 of its safety to this happy resemblance ; for its flesh is very good, and, in consequence, the 

 poor creature is dreadfully persecuted by the natives, as well as by the white hunters. The 

 cry of this creature is low and plaintive, and is thought to resemble the sound Ai. The head 

 is short and round, the eyes deeply sunk in the head, and nose large and very moist. 



The young of the Ai, as well as those of the other Sloths, cling to their mother as soon as 

 they are born, and are carried about by her until they are able to transfer their weight from 

 their parent to the branches. Several other species of Sloths are known to exist, but all are 

 similar in appearance and habits. 



The family BradypodidoB embraces the present living Sloths. They are especially confined 

 to the forests of Brazil, Bolivia, and Guatemala. Two species are known of the genus Cho- 

 Icejnis — the Two-toed and Hoffman's Sloths. 



The genus Bradypus includes one species — the Ai, or Three-toed Sloth. A good figure is 

 seen herein. Several small Sloths, embraced in the genus Arctopithectis, are indigenous in 

 South America. 



THE MONOTREMES. 



There are few animals which have attracted such universal attention, both from scientific 

 men and the reading world in general, as the Mullingong, Duck-bill, or Platypus, of 

 Australia. This little creature, the largest being but twenty -two inches in length, has excited 

 more interest than animals of a thousand times its dimensions, on account of its extraordinary 

 shape and singular habits. It is most appropriately called the Duck-bill, on account of the 

 curious development of the intermaxillary bones, which are very much flattened and elon- 

 gated, and their ends turned inwards in a kind of angular hook. The lower jaw is also 

 lengthened and flattened, although not to such an extent as the upper, and the bones are 

 covered with a naked skin. 



In the stuffed and dried specimens the "beak" appears as if it were composed of the 

 black leather taken from an old shoe, but in the living animal it presents a very different 

 aspect, being soft, rounded, and of a pinky hue at its tip, mottled with a number of little 

 spots. Dr. Bennett, to whom the zoological world is so much indebted for his researches into 

 the habits of this curious animal, kindly showed me some excellent drawings, which gave a 

 very different idea of the animal from that which is obtained by the examination of stuffed 

 skins. The beak is well supplied with nerves, and appears to be a sensitive organ of touch, 

 by means of which the animal is enabled to feel as well as to smell the insects and other 

 creatures on which it feeds. 



The Mullingong is an essentially aquatic and burrowing animal, and is formed expressly 

 for its residence in the water, or under the earth. The fur is thick, soft, and is readily dried 

 while the animal enjoys good health, although it becomes wet and draggled when the creature 

 is weakly. The opening of the ears is small and can be closed at will, and the feet are fur- 

 nished with large and complete webs, extending beyond the claws in the fore-limbs, and to 

 their base in the hind-legs. The fore-feet are employed for digging as well as for swimming, 

 and are therefore armed with powerful claws rather more than half an inch in length, and 

 rounded at their extremities. With such force can these natural tools be used, that the Duck- 

 bill has been seen to make a burrow two feet in length through hard gravelly soil in a space of 

 ten minutes. While digging, the animal employs its beak as well as its feet, and the webbed 

 membrane contracts between the joints so as not to be seen. The hind-feet of the male are 

 furnished with a spur, about an inch in length, curved, perforated, and connected with a gland 

 situated near the ankle. It was once supposed that this spur conveyed a poisonous liquid 



