42 
The South Australian Naturalist 
lions or projections. P, tasmanica (Tenison-Wood) is occasional- 
ly found. 'I’he valves of this species are shorter and broader 
than the common variety, and carry 8 or 10 rows of prominent 
hooked spines. 'Fhese wedge-shaped bivalves measure up to 15 
inches in length, all having a thinly-laid pearly interior — the shell 
itself being composed of minute hexagonal prisms. A rough dis- 
section ol the animal discloses a fine double-fringed mantle, and 
a set of powerful muscles connected to each valve, and to the 
byssiis. 'I’he Pinnas are planted firmly erect in the sand, and 
their ra/.or-like edges are capable of inflicting a severe wound, 
therefore making strong boots essential before any attempt is 
made to move among them. Examining one it is noticed that 
several I/aliotis cyclobates (Pcron) are clinging to it. This shell 
which measures about 1;J inches across, is of a comparatively glob- 
ose shape, wiih several white irradiations running across its dark 
brown surface, and having a brilliant iridescent interior. It is 
interesting to notice, if a specimen is turned over on its back out 
of water, the vigorous attempts made to right itself, the animal 
swinging its shell round in a half circle from side to side. Further 
examining the Haliotis one may find three or four small conical- 
shaped shells — Capuliis australis (Lamarck) — adhering, and sup- 
erimposed on the Capulus several juveniles of the same family, 
Another Pinna, in addition to the occupants already mentioned, 
may carry several beautifully colored Ischnochiton contractus 
(Reeve) or the slug-like Cryptoplax gunni (Reeve). The Crypto- 
plax lives for hours out of water, and, if given the opportunity, 
crawls laboriously about, anxiously, no doubt, seeking its native 
element. The little brown I schnochito7i juliodes also may be 
noticed sliding comparatively rapidly along the Pinna’s back, 
Conus anemone (Lamarck) is the next shell examined, being 
found inside the open, half sand filled valves of the dead Pinnas, 
C. ane?no7ie is one South Australia’s three Cones. While not 
comparable either in size or decoration with exotic specimens such 
as C. literatus, C. textile, or C. geographus , when its dull perio- 
stracum is removed it is quite a good looking specimen, colored in 
green, purple, brown and greyn This shell was observed to be 
living 24 hours after removal from the 'water, the blood-colored 
animal extending its foot, seemingly^ still hoping for a return to 
the natural order of things. Murex triformis (Reeve) is also 
found in company^ with the Conus. The prominent longitudinal 
ridges on this three-cornered shell represent periods of rest and 
erowth. Thk group gives (1) the univalve. Conus; (2) bivalve. 
Pinna; (3) multivalve. Chiton. The hammer-headed oy^ster— 
Malleus alhus (Lamarck) is plentiful. Tt attaches itself by its 
byssus to a stone or other object, and numbers are found in close 
