THE RECENT LUNG-FISHES 125 
Queensland as a plentiful food-fish, a “salmon” in size and 
taste, although, curiously enough, it remained undescribed 
until 1870 (Krefft, and Giinther). After this its develop- 
mental history was eagerly awaited, in the hope that it 
would reveal the affinities of the Dipnoans to the sharks, 
amphibians, and in general to the early chordates. About 
ten years ago Caldwell was sent to Queensland by the 
Fig. 129. — The South American lung-fish, Lepidosiren paradoxa, Natter. X }. 
(From NICHOLSON, after NATTERER.) A front view of the mouth is shown at 2. 
Royal Society, and succeeded in securing a set of the 
embryonic stages, but his results still remain unpublished. 
A second set of embryos was collected in 1891 by Semon, 
from whose recent paper a summary is later given (p. 198). 
The development of Ceratodus, however, as far as it is at 
present known, has proven in many ways unsatisfactory to 
the phylogenist ; its abbreviated growth stages cannot be 
