414 SCIENCE PROGRESS. 



The assumed generic identity of these two forms was the 

 most important new evidence brought forward by Forbes in 

 his paper supporting the hypothesis of the former existence 

 of an Antarctic Continent ; but in the paper just referred to 

 (35) it was shown that, as far as the birds are concerned, 

 there is no evidence that the Chatham Islands have been 

 united with any land area, and that the presence of two 

 similar flightless rails on two islands remote from one 

 another is no proof of any former land connection between 

 them. In such a case it seems far more reasonable to sup- 

 pose that both the islands may have been colonised by the 

 same or allied forms of flying rails which have subsequently 

 lost their powers of flight, owing to the very fact of their 

 insular conditions of life. An instance of this on a smaller 

 scale is found in the case of Tristan d'Acunha and Gouo-h 

 Islands, which are about 200 miles from one another and 

 about the same distance from the Cape of Good Hope. 

 Each of these islands is inhabited by a distinct species 

 of Gallinule (Porphyriornis), which closely resemble one 

 another and are incapable of flight ; yet no one has sug- 

 gested that on that account these islands were formerly 

 united by land, either with one another or to Africa. 



It is a fortunate coincidence that while the relationship 

 between Diaphorapteryx and Aphanapteryx was still in 

 dispute some additional remains of the latter were described. 

 These bones, together with those of many other species, 

 including the Dodo, Lophopsittacus mauritianus, Fulica 

 Newtoni, etc., were described by Newton and Gadow in 

 a well-illustrated memoir (36). Besides adding much to 

 our knowledge of previously known extinct birds, the 

 authors have been able to describe a number of new 

 ones. They have also published a figure of the restored 

 skeleton of the Dodo, which in several respects is more 

 correct than those which have previously appeared. The 

 whole of the remains described were obtained from the 

 Mare aux Songes, from which previously a large quantity 

 of Dodo bones had been collected. Besides the bones of 

 birds those of the large extinct lizard, Didosaurus, and 

 carapaces of Tortoises were found. 



