CHAP. IV.] ZOOLOGICAL REGIONS. 81 
arisen ; and it is hoped that these divisions will prove as satis- 
factory and useful to naturalists in general as they have been to 
the author. Of course, in a detailed study of any region much 
more minute sub-division may be required; but even in that 
case it is believed that the sub-regions here adopted, will be 
found, with slight modifications, permanently available for ex- 
hibiting general results. 
I give here a table showing the eve eet richness and 
speciality of each region as determined by its families of verte- 
brates and genera of mammalia and birds; and also a general 
table of the regions and sub-regions, arranged in the order that 
seems best to show their mutual relations. 
CoMPARATIVE RICHNESS OF THE Six REGIONS. 
VERTEBRATA. MAMMALIA. BIRDs, 
REGIONS. ie Peculi P Peculiae Pp 
Sey erates || Semen, (RA al eaters: (CNIS | cre 
| al | 
Palzarctic...| 136 3 100 35 35 174 EY / 33 
| Ethiopian ...| 174 22 || 140 90 64 || 294 | 179 60 
Oriental......| 164 1g 118 55 46 340 165 48 
Australian...| 141 30 72 44 61 298 189 64 
Neotropical...) 168 44 130 103 79 683 | 576 86 
Nearctic .....| 122 12 74 24 32 169 52 31 
TABLE OF REGIONS AND SUB-REGIONS. 
Regions. Sub-regions. Remarks. 
I. Palearctic... 1. North Europe. 
2. Mediterranean (or S. Eu.)) Transition to Ethiopian. 
3. Siberia. Transition to Nearctic. 
4, Manchuria (or Japan) Transition to Oriental. 
1. East Africa. Transition to Palearctic. 
2. West Africa. 
3. South Africa. 
4. Madagascar. 
II. Ethiopian ... 
