Sea Shells 
of New <ea 
land 
Plate VII 
25 
No. 
Plate VI 
No, 15 
the front margin, and rounded at the posterior Margin, 
The shell is somewhat raised in the centre and is sculptured 
with concentric ribs, which run completely round the entire 
shell, leaving a small elevated portion in the middle with 
a beak pointing backwards, The margin is thick, rounded 
and smooth. In length it may attain to two and a-half 
inches; in breadth a trifle over one and a-quarter inches. 
The animal bearing this shell is a somewhat unpleasant- 
looking creature of slug-like nature, large in comparison 
to the size of the shell, blue black in colour, and adhering 
firmly to the under surface of overhanging rocks, hiding 
beneath the seaweed, One naturalist describes it as “on 
apathetic animal,” and no one familiar with their habits 
can imagine them affecting the strenuous life. I particy- 
larly remember one individual strongly attached to two 
full-grown Acanthochites porosus, commonly known as 
butterflies, under a secluded fringe of weed, They all 
came away together with the exercise of a little force. As 
the Scutus is by nature a vegetable feeder, he could have 
had no sinister designs on his companions, and mere soci- 
able feelings being out of the question, we can only assume 
that sheer indifference to the presence of the Chitons ac- 
counted for the strange gathering, 
* Found in both Islands; Mount Maunganui. 
TROCHUS OPPRESSUS (trochus, a hoop ; oppressed). 
—This little shell is a quarter of an inch in diameter and 
almost of equal height. In colour it is “dark olive brown, 
or greenish” (Suter), or “purplish black” (Hutton). 
Sculpture consists of fine and numerous spiral striations, 
closely set together so that the intervening ribs are rounded 
and narrow. There are five or six whorls; the body whorl 
is slightly waisted, and has also a pronounced shoulder 
below the suture. The umbilicus is open and funnel- 
shaped, partitioned off from the aperture by a bowed and 
expanded columella. The ribs on the base are somewhat 
granular. 
Found at Takapuna; Mount Maunganui; East Cape; 
Lyall Bay; Taumaki Island, 
_ TROCHUS TIARATUS (éruchus, a hoop; tiaratus, 
like a tiara or Papal crown).—This shell, commonly known 
as a Top shell, is somewhat conical, of a pale yellowish- 
grey colour, sculptured with finely-beaded cords spirally 
wound round the whorls; some of the beads marked with 
dark brown, alternating with white and pale brown patches. 
The shell has in consequence a speckled or pepper-and-salt 
22 
