HISTORY OF ZOOPHYTOLOGY. 
17 
was he afterwards satisfied of the non-existence of animalcules, 
that he combated the opinion of those who maintained the con- 
trary, pointing out where the error lay in mistaking small in- 
sects which had crept into the sponge in search of food or shel- 
ter for the real inhabitants and fabricators of the zoophyte. Yet 
not the less was Ellis convinced of its animality ; — its chemical 
constituents and its structure were to him conclusive proofs of 
this fact, particularly when added to the signs of irritability he 
saw them exhibit when in a fresh state. “ I am persuaded,” 
he writes to Linnaeus, cc the fibres, intertextee. of sponges are only 
the tendons that enclose a gelatinous substance, which is the 
flesh of the sponge. Mr Solander and I have seen the holes 
or sphincters in some of our sponges taken out of the sea, open 
and shut while they were kept in sea-water ; but discovered no 
animal like a polype, as in the Alcyonium manus mortui.” And 
again — 66 I attended last summer in pursuit of the animals in 
sponges, but believe me there are none : but the whole is an ani- 
mal, and the water passes in a stream through the holes, to and 
fro, in each papilla.”* 
When Ellis published these discoveries, which form in fact 
an epoch in the history of natural science, "(* Linnaeus was in the 
* Lin. Corresp. Vol. i. p. 161 andp. 163. In a subsequent letter Ellis explains 
himself more fully. “ I am now looking into the nature of sponges, and think by 
dissecting and comparing them with what I have seen recent, and with the Alcy- 
onium manus mortua, that I can plainly see how they grow ; without trusting to 
Peyssonell’s account of them, which is printed in our Philosophical Transac- 
tions, wherein he pretends to tell you, that he takes the animal out of them, that 
forms them ; and that he put it into them, and it crept about through the mean- 
ders of the sponge. This kind of insect, which harbours in sponges, I have 
seen ; but sponges have no such animals to give them life, and to form them. 
Their mouths are open tubes all over their surfaces, not furnished, like the tubes 
of the Alcyonium manus mortua , with polype-like mouths or suckers. With 
their mouths they draw in and send out the water ; they can contract and dilate 
them at will, and the Count Marsigli has (though he thought them plants) con- 
firmed me in my opinion, that this is their manner of feeding. If you observe 
what he has wrote on sponges in his Histoire de la Mer, and the observations he 
has made on the Systole and Diastole of these holes in Sponges, during the time 
they are full of water, you will be of my opinion. Take a lobe of the officinal 
sponge, and cut it through perpendicularly and horizontally, and you will observe 
how near the disposition of the tubes are to the figure I have given of the sec- 
tions of the Alcyonium manus mortua in my plate of the Sea-Pens.” — Lin. 
Corresp. Yol. i. p. 79-80. 
f The Royal Society adjudged to Ellis the Copley medal, “ as the most 
B 
