INTRODUCTORY .- 
Sponges, which we now so clearly know as animals. 
were not many years ago regarded by most of our promi- 
nent naturalists, as belonging to the vegetable kingdom. 
Thus Owen, in the last edition of his work on the Anatomy 
of Invertebrates, published in 1855, omits sponges, thereby 
giving us to understand that they were quite beyond the 
pale which bounded the kingdom that he had under con- 
sideration. In fact, he alludes tothem several times in 
his book, as forms of vegetable life which produce free 
swimming spoors, as seen in some of the sea weeds. 
Even after the sponges had been fairly introduced 
into the system of the Zoologist, they received comparative- 
ly little attention. In fact there is scarcely any group of 
animals which are so widely distributed, and which are rep- 
resented by so many species as the sponges, which have 
been studied'so little by naturalists. What is true of 
sponges in general, is true of the sponges of North Ameri- — 
ca, especially of the West Indian and Florida waters. 
(5) 
