MJ 
(<a 
vase Worms, 
Contrary to the Crustaceans the 
worms are very poor in adaptive phe- 
nomena. No really good case of pro- 
tective resemblance appears to be 
known. I have observed one peculiar 
case which I think it worth while to 
describe, even though it cannot be re- 
garded as an instance of real protect- 
ive resemblance. 
On a small Gorgonid, dredged in 
ca. 25 fathoms off Jolo, was found 
the tube of a Serpulid, attached in a 
very peculiar way (Fig. 15). — Only 
the end of the tube is wound round 
a branch of the coral, and then it 
ST0ws straight out. The cortex of the 
coral grows over the tube, covering 
it completely, and soon the worm tube 
gets the function of the axis of the 
coral; the true tip of the coral branch 
atrophies and remains on the side of 
the worm tube; new side-branches of 
the coral arise directly from the cortex 
Covering the worm tube, which has 
thus become an integral part of the 
Coral. That a very good protection 
has been acquired in this way is evi- 
dent; and, of course, the fact that the 
branches with the worm-tube axis are 
differently shaped from the normal 
Fig. 15. A Serpulid, attached to a 
sorgonian. Nat. size. 
branches does not interfere with the protection afforded by the 
Polyps of the coral. The worm, itself, is not at all modified. 
VI. Echinoderms. 
The Echinoderms are also very poor in phenomena of protect- 
ive adaptation, probably because they are upon the whole not much 
Preyed upon by fishes or other animals against which protective 
