DUCKBILL AND HCHIDNA. 573 
in a mammary pouch, where the young hatch. The duck- 
bill also lays large eggs. The embryonic development is 
meroblastic, as in reptiles. The toothless jaws* are long and 
narrow in the Echidna, or broad and flat in the duckbill 
(Ornithorhynchus paradozus Blumenbach), where it is cov- 
ered by a leathery integument; the external ear is wanting. 
ris wa 
Fig. 494,—Skeleton of Hchidna hystriz.—From Brehm’s Thierleben, 
In the aquatic duckbill the feet are webbed, with claws 
of moderate size. It is covered with a softfur, and is about. 
half a metre (17-22 inches) long. Its : 
habits are like those of a muskrat, fre- 
quenting rivers and pools in Australia 
and Van Dieman’s Land, sleeping and 
breeding in holes extending from un- 
der the water up above its level into 
the banks, and with an outlet on shore. 
It lives on mollusks, worms, and 
water-insects. Young duckbills, five 
cm. long, have been found in their 
nests. , 
The spiny ant-eater (Figs. 493 and 
494) is represented by three species, 
the Echidna hystrix Cuvier, of Aus- 
tralia, #. Lawesii Ramsay, from Port 
Moresby, New Guinea, also by a re- QS iw” 63 
cently discovered form inhabiting the ae eiseieen of 
elevated portions of Northern New marsupial bones. sae 
Guinea, and called by Gervais Acanthoglossus Bruijnit. In 
these singular animals the bill is long and slender, tooth- 
* Rudimentary teeth occur in the embryo, in the place occupied by 
the plates (Poulton). 
