7 
have made rapid strides in their research, and the 
seemingly hidden mysteries of nature have been brought to 
light with wonder and admiration. Witness the sickly - 
looking maggot of to-day, which may be the active little fly 
of to-morrow, sporting in the sunshine as it flies from leaf to 
leaf ; or, the caterpillar of yesterday, the chrysalis of to-day, 
awaiting its transformation into the beautiful butterfly ? 
These objects are seen with the naked eye as we pass along 
the green lanes. Then what must be the amazement and 
wonder when the aid of the microscope is required to-trace 
out similar transformations in the smallest living organisms 
and the metamorphoses of the liver fluke cannot be viewed 
without interest, passing as it does such a large portion of 
time out of the bod}^ of the animal it finally inhabits ? 
* 
The distoma hepaiicum and distoma lanceolatum or liver flukes, 
are of a dark greenish, yellow-brown colour; flat, oblong, 
oval parasites averaging about one inch in length and half- 
'~an-inch in breadth at their widest part, anteriorly tapering 
towards the posterior extremity, and being covered by a fine, 
thin transparent skin, which on the hepaticum is raised into small 
sharp ^elevations pointing backwards, having two sucking 
orifices—hence their name distoma —one situated at the ex¬ 
treme end of the creature, and called the oriel sucker, which 
answers the double purpose of the inlet and outlet of the bile 
on which it lives ; the other is situated on the under surface, 
a little behind the former, and is called the ventral sucker, 
and from its arrangement is supposed to be used for at¬ 
tachment to the mucous membrane of the bile-ducts, as 
well as being a medium of progression, and found infesting 
the livers of most of our domestic animals, likewise hares and 
rabbits, and even man himself, but most commonly in 
