290 MR V. TATE REGAN ON THE 



III. No orbitosphenoid ; no opistliotic; no upturned vertebraj ; mesopterygoids 

 toothed (absent in Sulangidse). 



A. A mesocoracoid ; maxillaries dentigerous, entering gape . 4. Osmerida'. 



B. No mesocoracoid ; maxillaries dentigerous, entering gape. 



Head compressed ; mesopterygoid well developed, dentigerous ; ribs ossified. 



5. Retropinnatid^. 

 Head strongly depressed ; no mesopterygoid ; ribs not ossified 6. Salangidn'. 



C. No mesocoracoid ; maxillaries toothless, beliiml prajmaxillaries. 



Prajmaxillaries not extending whole length of maxillaries ; roof of myodome 

 unossified ; no adipose fin . . . . . . 7. Galaxiida}. 



Pntmaxillaries nearly reaching extremities of maxillaries ; roof of myodome 

 ossified ; an adipose fin ..... 8. Haplocliitonida^ 



The Argentinid;e and Microstomidpe are inhabitants of rather deep water, but the 

 rest are littoral fishes, many of them entering fresh water and often forming colonies, 

 races, or species confined to fresh water. 



It is of some interest to note that the Galaxiida) and Haplochitonidfe are related to, 

 but more specialised than, the Osmeridge, or Smelt family, of northern seas. Retropimia, 

 from the eoa.sts and rivers of Australia and New Zealand, is still nearer to the Galaxiidse 

 and Haplochitonidte ; both these families occur in Australia, Tasmania, New Zealand, 

 South America, and the Falkland Islands, and there are even two species of Galaxias 

 at the Cape of Good Hope. All the species enter fresh water, and the majority seem 

 to be strictly fluviatile or lacustrine, but in a few cases species of Gahi.rias have been 

 observed in the sea. 



In 190G {Proc. Zool. Soc, 1905, ii. pp. :]63-384, pis. x.-xiii.) 1 published a 

 revision of the Galaxiidse, and then wrote : — 



"The occurrence of (Tf?ya.n«.>f inaculatus in the sea has been recorded by A^alen- 

 ciENNES and by Piiilippi, off the Falkland Islands and f)ff the coast of Chile respectively. 

 The observations of Johnston in Tasmania and of Huttun and Clarke in New Zealand 

 are to the effect that Galaxias atteimatus descends to the sea periodically to spawn. 

 Mr Rupert Vallentin has seen shoals of little fishes, which I identify with the 

 Galaxias gracillimus of Canestrini, in the sea at the Falkland Islands. Recently 

 Galaxias In-evijnnnis also has been found to lie marine, G. hollansi, described by 

 Hi^tton from the Auckland Islands, proving to be identical with this species." 



Waite {Suhaiit arctic Islands of New Zealand, p. 586) has recently shown that 

 IIiitton's conclusion as to the marine habit of G. hrevipinnis was probably incorrect. 

 Eioenmann {Rej). Princeton IiJxped. Patagonia, in., Zool., 1909, p. 274) says of G. 

 gracillimns : " This is undoubtedly the young of attenuatus " ; and if this opinion, wliich 

 does not appear to be the result of an examination of specimens, bo accepted, tlie known 

 marine species of Galaxias would be reduced to two only. 



In my revision I distinguished G. gracillimus from G. attcimat-us l)y the more 



