POST LARVAL STAGES OF AUSTRALIAN FISHES. 
139 
At a length of 12 to 16 millimetres the body depth has increased in 
proportion and is approximately equal to the head length, which is 3^ to 3f 
in the total length. In adults the head length decreases to about 4^ and the 
body height increases to 2§ in the total length. The eye diameter decreases 
from 3 to 3£ in the head length during growth from 12 to 1 6 millimetres. 
Specific diagnosis was arrived at by following through changes in 
proportions and pigmentation in a very complete series of many score of 
specimens of intermediate sizes ranging from planktonic larvae to adults. 
Possession of the average fin formula of D. XII, 11 ; A. Ill, 8-9 separates 
these young from those of A. sarba. 
2. AUSTROSPAEUS SARBA (Forskal). TAR WHINE. 
o 
Spams sarba Forskal (1775), p. 31. 
Review of the literature dealing with the Tarwhine, Austrosparus sarba 
(Forskal) reveals that little direct observation has been made in respect to its 
•spawning season. Roughley (1916) indicates that it occurs during early summer. 
The eggs and larvae are entirely unknown. The writer has noticed that 
postlarvae, identifiable by their fin counts as being this species, occurred 
simultaneously with those of the Bream (A. australis) in the Noosa River 
plankton during June 1940. Also, larger postlarvae occur simultaneously with 
those of A. australis in the weedy shallows and creeks near the mouths of 
Noosa River, Bribie Passage and other east coast estuaries. This evidence rather 
suggests that both these Sparid species spawn during the same extended season, 
which in southern Queensland during 1944 was the winter months. 
Several postlarvae, varying in size from 11-0 to 12*4 millimetres, have 
been obtained in the Noosa River plankton in June 1940, and another specimen 
11-5 millimetres long was taken in a surface plankton haul at Caloundra on 
12/11/44. The smallest postlarval Tarwhine collected with the seine net also 
measured 11-5 millimetres and was taken in shallow water in the creek joining 
Weyba Lagoon to Noosa River on 25/6/44. All of these postlarvae have the 
typical planktonic facies indicated in text fig. 2 A. At this stage of development 
they closely resemble in appearance postlarval A. australis of similar size. Their 
distinctive fin formula, namely D. XII, 13 ; A. Ill, 11 which is two or three 
rays greater in both soft dorsal and anal fin counts than A. australis , is the 
most reliable clue to their diagnosis. These postlarvae are quite transparent 
and their black pigment is arranged similarly to that of A. australis at the same 
stage of development. The ventral linear series that extends from the anus 
to the base of the caudal fin is practically identical. The chroinatophores of 
the head are smaller in size and fewer in number and do not extend as far 
back behind the eye as those of Bream. There is an internal lining of dark cells 
on the dorsal surface of the visceral cavity and an internal longitudinal series 
situated dorsally to the vertebral column and extending from the perpendicular 
at the anus backwards to the base of the tail. The head is shorter than that 
of the Bream, being 4^ to 4^, and the greatest body height 4f in the total length. 
The eye diameter is similarly about 3 in the head length, but the perpendicular 
measurement between the upper margin of the eye and the top of the head 
is much greater in A. sarba at this stage. 
