10 
THE COMMON RED WORM OF OUR RIVERS. 
(tubifex rivulorum). 
BY E. RAY LANKESTER. 
0 river lias enjoyed so large a share of odium as our old 
friend Father Thames. The medical world anathematizes 
its noxious exhalations ; our witty contemporary “ Punch ” ever 
and anon cracks a joke at its expense ; but like all old folks w'ho 
have jogged along quietly for a series of years in the same 
smooth channel, our patriarch gives little heed to the insults 
that are heaped upon his grey head, or retaliates upon his 
assailants by giving them an additional dose of poison. 
However we may agree with its accusers, from a sanatory 
point of view, we don’t mean to fall out with the good old 
stream that has often-times served as our high road eastwards 
or westwards ; we mean rather to court its favour and earn its 
good wishes, for we have found something in the midst of its 
filth, which will, we trust, redeem it from utter condemnation, and 
will serve to show that there are not only “ books in running 
brooks,” but that even muddy rivers yield themes for study 
and investigation. 
The living object which we are about to describe is found 
not alone in the river Thames, but also in many others. We 
have, however, obtamed it from our own stream, near Waterloo 
Bridge, at low-tide, and it is then so plentiful as to tinge the 
mud, which serves as its habitat, with a dull-red colour. 
Doubtless our readers will be somewhat incredulous when we 
assert that repulsive as is the locality in which it occurs, nay, 
distasteful (to use a mild expression), as is the object itself, a 
worm, to the large majority of unscientific persons, this one is 
really beautiful as seen under the microscope. 
It resembles a crystalline snake, both in appearance and 
movement, through whose hyaline skin all the internal organs 
of life are seen in active operation. Not only, therefore, is it 
interesting as a microscopical object, but its transparent enve- 
lope, which reveals its internal anatomy, and the great facility 
with which it may be obtained, point it out as an object of 
especial value to young students in the anatomy of the lower 
animals ; and we trust that our short review of its various parts 
