THE ANATOMY OF PHORONIS AUSTRALIS. 125 
The Anatomy of Phoronis Australis, 
By) 
William Blaxland Benham, D.Sc., 
Demonstrator in the Zoological Laboratory of University College, London. 
With Plates X, XI, XII, and XIII. 
INTRODUCTION. 
Wuen I commenced the study of Phoronis, at the sug- 
gestion of Professor Lankester, in October, 1887, I had at 
my disposal only some specimens of the small species from 
Naples, but Mr. W. H. Caldwell, hearing of my intention 
to investigate the anatomy of the animal, most readily and 
very generously gave me a number of large species, Ph. 
australis, which he had brought from Australia. These are 
very well preserved, and are of such a size that it is possible 
to dissect them, and to observe, by this means, certain points 
in the anatomy. I wish here to express to Mr. Caldwell my 
most hearty thanks for this kindness. 
I had practically completed this memoir when Professor 
MclIntosh’s description of Ph. Buskii appeared in the 28th 
vol. of the ‘“ Challenger” Reports’ (19). He there gives a 
history of the literature on the subject, which renders it 
unnecessary for me to give such a detailed account of it as 
I had intended, and I shall therefore merely refer to some 
of the more important facts previously observed. Indeed, 
the appearance of Professor McIntosh’s memoir almost in- 
duced me to give up the idea of publishing my own account, 
but as I can add some new facts—more especially as regards 
