NOTES. 45 
more beautiful than in the adult, in some the primary spines 
often exceeding three times the length of the diameter of the tests, 
are of a rich purple or claret color beautifully ringed with white. 
The specimens alluded to were dredged off a sandy and rocky 
bottom in 8 fathoms of water, near the “ Bottle and Glass ” 
reef, in Port Jackson, and also off Shark Reef and Bradley’s 
Head, many secreted in the folds and angles of large Sponges 
and Ascidians. The spines of the adults are of a rich uniform 
dark claret color, very brittle and hollow. These Urchins frequent 
the reefs and rocky shores just below low-tide mark, where they 
obtain their food; they progress with considerable rapidity for 
an Urchin when once disturbed, until they find a secure retreat 
in some crevice of the rocks, from whence it is difficult to remove 
them without destroying either the spines or test. I notice that 
the spines of those from the outside reefs, where they are 
exposed to the wash of the sea, are shorter and somewhat 
rounded at the tips, while those taken from the quiet waters 
inside have larger and more pointed spines. They are gregarious, 
many being found together, and frequent shallow waters. The 
broken spines are readily repaired, the new tips growing rapidly. 
It is this species, perhaps more than any other Urchin, that 
becomes food for the Port Jackson Shark, Heterodontus 
galeatus ; the more common species H. philipi also occasionally 
feeds on them, the teeth of both species becoming stained of a 
beautiful pink or rose color. These Sharks frequent the 
reefs where the Echini abound, and it is quite probable many 
other species of Echinodermata supply them with food, their 
strong dorsal spines are frequently ground down to the surface 
of the fins, by their searching for food under the shelving rocks. 
The peculiar pigment or dye contained in the spines and within 
the test itself is worthy of investigation. I know of no other 
species on our coast which has this peculiarity. In cleaning 
the tests the fingers and nails become stained with the pigment, 
which is very difficult to remove. 
ECHINOTHRIX CALAMARIS. 
I have never seen any authentic specimen of this genus from 
the N.S. Wales coast. 
HETEROCENTROTUS MAMMILLATUS. 
ECHINOMETRA LACUNTA. 
The former is a very common species throughout the Pacific 
Islands; the latter, although found so near at hand as Lord 
Howe’s Island, has not, as far as I am aware, yet been obtained 
on the coast of N.S. Wales, although we have specimens from 
Port Denison, and | have heard of its being found as far south 
on the coast as Wide Bay, in Queensland. 
