79 
Careful questioning of the students who first uncovered the layer of 
footprints, and close study both in situ and of a series of photographs of 
the footprints seemed to justify the idea of two distinct animals and that 
one was a dinosaur with a stride of 7 feet, and thus for the first time 
evidence of these animals in the Triassic seemed definite. 
Subsequently other individual footprints were collected and the 
opportunity was taken during June of this year to show all the evidence 
to Professor K. Caster from Cincinnatti, who has had a large experience 
with fossil tracks of many forms. Professor Coster agreed that here we 
had definite evidence of there being not only Triassic quadrapedal, but 
also bipedal Dinosauria in Queensland and thus we have been able to 
extend the range in time of these animals here bock from the middle to 
the beginning of the Mesozoic. 
The footprints mentioned range from 3^' to 1 " long. 
A NOTE ON THE ALGAL FOOD OF THREE MARINE FISH 
FROM SOUTHERN QUEENSLAND 
Margaret Martin and Barbara Winks 
Animal life in the sea is basically dependent upon plant life, either 
directly or indirectly. In many cases the larger fish prey on the smaller 
species which in turn may be dependent on planktonic Crustacea which 
derive their food from microscopic algae such as diatoms. However, a 
few species of fish feed directly on the larger algae, and the stomach 
contents of three such species were examined. One of these, a Morwong, 
was caught on a reef off Mermaid Beach (April, 1955), and the other 
two, Microcanthus strigotus Cuv. & Val. and Acanthurus matoides (Cuv.), 
were taken at Point Danger from a lower littoral pool about eight feet 
deep containing abundant attached algae. The algae recovered from the 
stomachs of these fish and identified are as follows: — 
Plectorhynchus sp. (''Morwong'"). The one specimen examined contained 
mainly the sea lettuce, Ulva lactuca L. 
Microcanthus strigatus ("Stripey"). Of two specimens examined, one had 
no gut content, but the alimentary tract of the other contained 
quantities of algae. Enteromorpha sp. constituted the bulk of this 
algal material but the following genera also were recognised: — 
Oscillatoria sp., Chaetomorpha sp., Sphacelaria sp., Erythrotrichia sp., 
Polysiphonia sp., diatoms. 
Acanthurus matoides. The predominant algal species present in the 
stomach was Enteromorpha sp., together with fair quantities of 
Ectocarpus sp. Other Identified algae present in small quantity were 
diatoms, Sphacelaria sp., Acrochaetium sp., Polysiphonia sp., and 
Cladophora sp. 
The presence of large numbers of diatoms in the stomach contents 
of these fish does not necessarily indicate their deliberate ingestion, since 
many diatoms are epiphytic, and many were, in fact, found attached to 
the fragments of larger algae in the stomach. Similarly, some of the 
smaller filamentous algae present occasionally may have been taken in 
solely because of their close association with algae more desirable from 
the point of view of the fish. 
From the proportions of the various algae found in the alimentary 
tract it seems likely that both the Microcanthus and Acanthurus showed a 
preference for Enteromorpha at the time they were taken. It is of 
interest to note that species of this algal genus are sold os bait for the 
black bream, Gireila tricuspidata (Quoy and Gaimard), during the winter 
months in Queensland. 
