40 BIRD GALLERY. 



[Case 22.] food and for the sake of its oil. Numerous forms allied to this genus 

 have already become extinct, such as Aphanapteryx from Mauritius 

 and Leguatia gigantea from Rodriguez, which is described as standing- 

 six feet in height and having a body as large as that of a Goose. 



Other genera, such as the Purple Gallirmles (Porphyriola, Porphyrio 

 (329-332) and Notornis), are remarkable for the beauty of their plumage, 

 the great size of their bill and frontal shield, aud the length of their 

 toes. The celebrated " Moho " (Notornis mantelli), one of the most 

 interesting of the Purple Gallinules, is all but extinct. It is unable to 

 fly, aud has now entirely disappeared from the North Island of New 

 Zealand, but in the South Island three have been obtained during the 

 past century, one as recently as 1881, and a few may still exist in remote 

 parts of the country. Strangely enough the species was first described 

 by Owen from an imperfect fossil skull, and was at that time believed to 

 be extinct. Shortly after, however, a living specimen was captured, to 

 be followed by the others already referred to. Allen's Purple Gallinule 

 (P. alleni) (329 a) has occurred once at Yarmouth. The common British 

 Moorhen or Waterhen (Gallinula chluropus) (327) is nearly related to 

 the Purple Gallinules, though its colouring is much less brilliant. The 

 Coots (Fulica), of which the common Coot (F. atra) (334) is the best 

 known, may be recognised from the rest of the family by the broad lobes 

 to the toes, their feet bearing a strong resemblance to those of the 

 Grebes. They are all good swimmers, spending the greater part of 

 , their life on the water, and the species are distributed over most of the 

 world, though the majority belong to the South American region. 



Family II. HELIORNITHID.E. FINFOOTS. 



This family is represented by certain aberrant types undoubtedly 

 allied to the Rails, in spite of their curiously Grebe-like form. 

 Altogether three genera are recognised, two of which belong to the Old 

 World and the third is confined to South America. This latter genus 

 includes a single species of Finfoot (Heliornis fulica) (337). Peters's 

 Finfoot ( Podica petersi) (336) represents the Old World forms. 



Order VI. PODICIPEDIFORMES. 



Family PODICIPEDID^E. GREBE*. 



[Case 21.] The birds which constitute this Order are an extremely interesting 

 group on account of the profound modifications which the skeleton has 

 undergone in adaptation to the requirements of a purely aquatic life. 



The bones of the hip-girdle have become elongated and laterally com- 

 pressed to a remarkable degree. The thigh-bone is extremely abbreviated, 

 so that the legs are set very far back near the hinder end of the body, a 

 position which ensures the maximum of power when swimming, but 

 which leaves the bird almost helpless on land The front toes are 



