S.A. NAT., VOL. XVl. 
March 24, 1937. 
47 . 
LIFE AT THE EDGE OF THE SEA. 
By Keith Sheard 
(Hon. Assist, in Zoology to the South Australian Museum). 
Notes on the Collecting of Marine Invertebrates. 
A glance through the research cabinets of the Australian 
Museums, shows that while amateur collectors, as opposed to 
the professional workers in the various groups, have played a 
large part in the building up of most of the collections, those 
representative of the Marine Invertebrates, excluding the Mollus- 
ca, are mainly due to well organised expeditions or to the efforts 
of very few staff workers. With the best will in the world, the 
collector brings his gatherings in to the Museum, or builds a 
series for himself, but because he is unaware of the wealth of 
life at the tide's edge and is ignorant of the habits of that teem- 
ing population, his collections are merely repetitions of a few 
of the most obvious forms. 
The result of this is the literal fact that more is known of 
the invertebrate fauna of Antarctic seas than is known of the 
inhabitants of the reefs and tidal zones of our own land. Yet 
with very little coaxing, the rocks and sands and seaweeds can 
be induced to give up their secrets, secrets rich and rare enough 
to satisfy the most exacting. 
The collecting methods themselves are simple, but like most 
simple methods, effective. 
Their improvisation by the Director of the South Australian 
Museum (Mr. H. M. Hale), has resulted in very extensive ad- 
ditions to our knowledge of the coastal fauna. 
The first step is to learn the lay-out of the littoral zones 
of life. 
High up on the beach are the rows of decaying seaweed, 
homes of small amphipodan Crustacea, the Talitrids. Lower, on 
the line of the tide, come Marine Worms, various Mollusca, 
scavenging Cumacea, Amphipods, and Isopods, with sometimes 
armies of small crabs. The rule seems to be that the sand must 
not be too hard or too soft with the grains neither too large nor 
too small, and there appears to be, even given this ideal beach, 
correlation between the shore life and type of weed on the sea 
bottom opposite. 
Mr. B. C. Cotton and the writer visited the beaches between 
Outer Harbour and Marino and found that the hard packed sands 
Hanked by Estuarine weed of a low iodine content, between the 
