70 THE LINGULIDH OF THE QUEENSLAND COAST. 
the valves may undergo some distortion during drying. 
All the foregoing measurements, however, were taken from 
preserved animals. 
The sizes mentioned and the figures published for Z. 
anatina by Davidson, Yatsu and others show a ratio of 2.2. 
Sowerby’s fig. 3, has a ratio of 2.4, while figs. 9 and 10 
(brown and dark varieties respectively) show a ratio of 2.1. 
L. bancroftti then can usually be distinguished from ZL. 
anatina, which it closely resembles in most of its shell 
characters, by its 1atio of length to breadth being rather 
less. 7.e., the shell is relatively somewhat broader. Sowerby’s 
figs. 9 and 10 are very suggestive of our species. 
In L. murphiana, the other Queensland species with 
which the shell might be confused, the ratio is about 2.3, 
and, moreover, the adult shell is longer, thicker, more 
mineralised and the coppery colour more pronounced. 
Besides, just distally from the umbones, a section of the 
paired valves is more rounded than in L. bancrofti, a de- 
pressed area being present on each side of the mid-region 
of the valve in the latter species. There are also. marked 
anatomical differences to be noted later. 
The proportions correspond with those of L. jaspidea, 
viz., 2.0, and L. reevei, 2.1 (Davidson pl. 28, fig. 23, 24 and 
fig. 18 respectively), but the form is quite different in the 
three species. In young individuals the shell is sufficiently 
transparent to allow one to see the arms,«pallial sinuses, 
nephridia, rectum, liver and muscle impressions. The 
anatomy of small and medium sized specimens can be easily 
studied in Canada balsam after prolonged decalcification 
in rather strong acid acohol (70 per cent. alcohol with 3 
per cent. HC1.) followed by gradual dehydration and clear- 
ing in clove oil. The use of a weak solution of Ehrlich’s 
or Delafield’s hematoxylin followed by careful and pro- 
longed decolorisation, gives a very good result. 
The muscle scars are arranged as in L. anatina. No 
marked submarginal scar for the insertion of the sete 
musculature was recognised. King (p. 12, fig. 5) did not 
observe it in L. anatina. The deltidial region (text-figure 
6) resembles in most details that described by this author 
for L. anatina. 
