ANNIVEESAEY ADDRESS OF THE PRESIDENT. 79 



B. Arcifera division. 



1. Tropical American region. 



2. Australian region. 



The limits are the same as Wallace's. It should be mentioned, 

 however, that New Zealand can scarcely be assigned to the Aus- 

 tralian region, for its only Batrachian belongs to a family not known 

 to occur in Australia. Madagascar, too, has strong claims to 

 separation as a distinct region. 



Dr. Giinther also, in the ' Encyclopaedia Britannica ' and in his 

 * Introduction to the Study of Eishes ' (1880, p. 217), proposed a 

 scheme of distribution for the freshwater members of the class 

 ' Pisces.' The following are the divisions : — 



I. Northern zone. 



1. Europo-Asiatic or Palaearctic region. 



2. North- American or Nearctic region. 



II. Equatorial zone. 



A. Cyprinoid division. 



1. Indian region. 



2. African region. 



B. Acyprinoid division. 



1. Tropical American region. 



2. Tropical Pacific region (Australia, &c.). 



III. Southern Zone (Patagonia, Tasmania, and New Zea- 



land). 



It will not be necessary to dwell long upon the Invertebrata. 

 They have received less attention than Yertebrates, and except in a 

 very few groups, more remains to be done both in ascertaining their 

 distribution and in determining their structural relations. Wallace, 

 in his work on Geographical Distribution, states that the Lepidoptera 

 and the best-known families of Coleoptera have approximately the 

 same distribution as mammals and birds ; but he admits some 

 differences — for instance, the occurrence in temperate South America 

 of a well-marked insect-fauna allied to that of the north temperate 

 zone, and not to neotropical types. 



Among the land and freshwater Mollusca, the Pulmonata, and 

 especially the HeliGidoe and Limacidce, need thorough revision. 

 Without much additional information concerning the animals (the 

 shells alone having been described in a great majority of species and 

 even in many genera) no accurate knowledge of the affinities of 



