ORNITHOKHYNCHIDiE. MAMMALIA. TaCHYGLOSSID/E. 
Tlie Duck-bill feeds on small molluscous animals, 
various aquatic larvae, and especially on water-bugs 
belonging to the genus Naucoris, which abound in 
the running streams and lakes of Australia. The most 
interesting account of the habits of this animal yet 
placed on record, is that given by Mr. Bennett in the 
first volume of the Zoological Society’s Transactions. 
Speaking of one which he kept in a semi-captive state, 
occasionally tethering it to a stake by the river’s side, 
he tells us that “ it was exceedingly lively, swam in 
the centre of the stream, and appeared in excellent 
health and spirits. The water at one part of the 
river being very clear, I saw its movements distinctly 
rmder the water. On diving, it sank speedily to the 
bottom, swam there for a short distance, and then rose 
again to tire surface ; it ranged the banks, guiding itself 
in its progress according to the impressions received by 
the mandibles, which appeared to me to be used by it 
as very delicate organs of touch. It seemed to feed 
well ; for whenever it inserted its beak into the mud 
it evidently procured some food from thence, as, on 
raising the head, after withdrawing the beak, the man- 
dibles were seen in lateral motion, as is usual when 
the animal masticates. Although several insects were 
basking and fluttering about the surface of the water, 
close to it, no attempt was made to capture them, either 
from its not seeing them, or from its preferring the food 
which the mud afforded. The motions of the mandi- 
bles in this animal, when seeking its food in the mud 
and water, are the same as those of a duck when feed- 
ing in similar situations. After feeding it would lie 
sometimes on the gi’assy bank, and at others partly in 
and partly out of the water, combing and cleaning its 
coat as usual with the claws of the hind feet. After 
permitting it to swim, feed, and clean itself for an 
hour, it was replaced, although with great reluctance 
on its o\vn part, in its box ; it did not, however, as 
before, betake itself to repose, but commenced and 
continued a scratching on the sides of the box.” 
During sleep the duCk-bill rolls itself up in the form 
of a ball. For this, and many other mteresting 
facts, we are indebted to Mr. Bennett, who has also 
given us a full accoimt of the form and extent of the 
burrows which these animals construct in the banks 
of rivers. One of these burrows measm'ed fully 
twent}'' feet in length. It commenced in some long 
grass about five feet from the water’s edge, passed 
upwards in a sei’pentine direction, terminating near 
the surface of the ground in a rounded excavation, the 
lower part of this hollow forming a nest of dried grass 
and weeds. In this particular burrow Mr. Bennett 
captured an unlucky ornithorynchus, which, on being 
drawn out by the leg, manifested the most alarming 
evidences of fear, its heart palpitating violently. It did 
not scream, or make any attempt to bite ; during its 
subsequent captivity, however, it frequently uttered a 
soft growl during the night, at which time it also made 
vigorous efforts to escape. 
219 
Family II.— TACIIYGLOSSIDiE, 
The members of this family are at once distinguished 
from the former by the mixed spinous and hairy char- 
acter of their fur, as well as by the circumstance of 
their possessing a slender subulate muzzle and a merely 
rudimentary tail. On closer examination we find tliat 
the jaws are entirely edentulous, the palate being 
armed with several rows of small spines directed 
backwards. A more significant character is founded 
on the form of the tongue, which is long, narrow, 
rounded, and very extensile — hence the family name 
above given — closely resembling the lingual organ in 
their placental representatives, namely, the true ant- 
eaters and pangolins. The pentadactylous feet are 
short and thick, the digits being furnished with power- 
ful falciform claws adapted for burrowing. The second 
aud third digits of the hind feet are particularly long. 
The stomach is simple, capacious, and spherical when 
distended. The coecum is moderately developed. 
THE POKCTJPINE ANT-EATER {Tachyglossm Hys- 
trix), or Australian Hedgehog of the colonists, is a 
native of New South Wales and Van Diemen’s Land, 
but is now rather rare in the first named locality. It 
is maintained by some, on gi'ounds apparently tenable, 
that the forms proper to the two habitations are 
distinct species; but others consider the differences 
observable insufficient to prove a separate origin. 
Without offering a positive decision, we strongly incline 
to the belief that they are different animals, the form 
known as the Van Diemen’s Land species ( Tachyglossus 
setosus) — which, however, is not peculiar to that island, 
according to the testimony of Mr. Waterhouse — being 
pro\flded with small and narrow digits, as compared 
with those of T. Hystrix, whilst the hairy appendages 
of the skin are also longer, the spines, on the other 
hand, being relatively short. Other minor differences 
likewise exist. These animals are about the size of 
our common hedgehog, varying in length from fourteen 
to eighteen mches. The hairy portion of tlie skin 
exliibits a chestnut colour, the spmes being whitish 
except at their tips, which are black. Like hedgehogs, 
they roll themselves up when attacked on the open 
ground ; but their safety is usually more effectually 
secured by burrowing in the earth, or by entermg a 
previously constructed tunnel. These animals feed 
upon ants, captured by the protrusion and subsequent 
retraction of their extensile glutinous tongues, after 
the manner previously described in our account of the 
typical edentate ant-eaters or myrmecophagas. 
Those who desire more extended information respect- 
ing the structure and economy of the monotreme mar- 
supials, are referred to Professor Owen’s elaborate 
article “ Monotremata,” contained in the third volume 
of Dr. Todd’s Cyclopaedia of Anatomy and Physiology ; 
and also to Mr. Gould’s large folio work on the 
“ Mammals of Australia.” 
END OF MAMMALIA. 
