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TRANSACTIONS OF THE AMERICAN PHILOSOPHICAL SOCIETY 



gestive of larval conditions. The elongate frontals are only on the sides of the brain and 

 there is a very large elongate median fontanelle occupied by the swollen brain. The 

 supraoccipital is wide and flat, widely separated from the parietals; parietals much reduced; 

 the alisphenoids are large and the orbitosphenoid absent. 



The skull as a whole is extremely unlike that of Galaxias and Swinnerton rightly 

 concludes (1903, p. 70) that this fish is not related to the Galaxiidae (to which it had 

 originally been referred by Boulenger), but is a specialized member of some other offshoot 

 of the malacopterygian stock. Tate Regan (1929, p. 313) puts it near the Chanidse. 



SOC 



Galaxias attenuatus 



G, truttaceus 



Fig. 50. Galaxias attenuatus. After Swinnerton. 



Galaxias. — A wide-ranging genus in New Zealand, Australia, South America and South 

 Africa. All but one species (G. attenuatus) live in fresh water, but this form is marine and 

 widely distributed in the southern hemisphere. Boulenger (1910, p. 607) interpreted this 

 fact as an indication that the group was originally marine and had invaded the fresh waters 

 from the sea. MacFarlane (1923, p. 360), on the other hand, regards the Galaxiidae as 

 indigenous to an ancient antarctic hemisphere, which later sank and of which the existing 

 lands of the far south are but fragments. In either case, Galaxias (Fig. 50) is on all 

 accounts an important archaic type in the history of fishes. 



The osteology of Galaxias attenuatus has been described by Swinnerton (1903). The 

 absence of the mesocoracoid arch, the simple unforked shape of the posttemporal, suggest 

 relationship rather with the Iniomi and Haplomi than with the Isospondyli, and Boulenger 

 refers them to his comprehensive order Haplomi. 



The cranial table is widened, the fiat supraoccipital being well separated from the 

 frontals by the large parietals. The frontals are wide, orbits large, nasals exceptionally 

 large and fiat; the prefrontal (parethmoid) with large preorbital buttress and the olfactory 

 fossa unusually large. The jaws are of fair size with conical teeth, the well developed 



