IO 



HISTORICAL AND GEOGRAPHICAL 





as a whole ; and among the Reptiles and Amphibians the Dipsadomorphidse 

 (Tree Snakes), Elap>idse (Coral Snakes), Iguanidse (Iguanas, &c), Tejidse 

 (Greaved Lizards), Alligcctoridse (Alligators and Caimans), Dendrobatidse 

 (Solid-chested Tree-Frogs), Hylidse (Typical Tree-Frogs), Pipidse (Surinam 

 Toad, &c), and others. 



Mexican Sub-Region.— In the richness of its fauna this Sub-region falls 

 little short of the Brazilian, for it possesses representatives of 127 families 

 of terrestrial Vertebrates. This number is made up as follows : Mammals, 

 24 ; Birds, 67 ; Reptiles, 26 ; and Amphibians, 10. There is little peculiarity, 

 only two families— both Reptilian— being confined to the sub-region, namely, 

 Xenosauridse. and Dermatemydidse (Mud-Terrapins), which contain only one 

 and four species respectively. Characteristic of this area are two species 

 of Tapir (Tapirus bairdi and dowi), which are the most northerly represen- 

 tatives of the family in the New World. The following families appear 

 to have their metropolis in this Sub-region: — Procyonidse (Raccoons), 

 Momotidse (Motmots), Odontophoridse (American Partridges), Anguidse 

 (Slow- Worms), and Plethodontidse. 



Antillean Sub-region. — Since this area is wholly made up of islands, 

 most of which are small, it is hardly surprising to find that the number of 

 families of terrestrial Vertebrates is much inferior to that in the other por- 

 tions of the Neotropical Region. Some 76 families in all occur in the Sub- 

 region. They are apportioned as follows :— Mammals, 7 ; Birds, 47 ; Reptiles, 

 16; and Amphibians, 6. Only two are peculiar, namely, one of Mammals, 

 and one of Birds. These are the Solenodontidse (Solenodons), of which only a 

 couple of species are known, and the Todidse (Todies), of which there are five. 



There is a remarkable absence of Mammals in this, as in other insular 

 Sub-regions, for there are no Primates, Carnivora, Ungulata, or Edentata. 

 The only Rodents are the Octodoniidse (Spiny Mice), represented by about 

 half a dozen species of Capromys, a genus practically peculiar to the West 

 Indies ; and a few Muridse belonging to the sub-family Sigmodontinse. The 

 Birds are mainly of a Neotropical character, but the following important 

 families are quite absent: Phytotomidse (Plant-Cutters), Pipridse (Mana- 

 kins), Dendrocolaptidse (American Creepers), Formicariidse (Ant-Thrushes), 

 Rhamphastidse (Toucans), Momotidse (Motmots), Gracidse (Curassows, (fee), 

 Tinamidse (Tinamous), and Rheidse (Rheas). Lastly, among Butterflies, the 

 typically Neotropical Brassolidse, Euselasiidse, Lemoniidse, and the genus 

 Morpho, are totally unrepresented. 



Number of Families of terrestrial Vertebrates in the Neotropical 

 Eegion and its Four Sub-regions. 





Mammals. 



Birds. 



Reptiles. 



Amphibians. 



Total. 



Neotropical Region in General 



Chilian Sub-region ... 

 Brazilian ,, 

 Mexican ,, 

 Antillean ,, 



32 (10) ' 



23 (1) 

 27(2) 

 24 

 7(1) 



80 (23) 



53(1) 

 71(4) 

 67 



47(1) 



29 (2) 



17 

 23 



26 (2) 

 16 



14(4) 



12(2) 

 10 

 6 



1 55 (39) 



100 (2) 



133 (8) 



127 (2) 



76(2) 



The figures in parentheses indicate the number of peculiar families. 



VI. NEARCTIC REGION. 



Extent. — The Nearctic Region embraces the whole of North America 

 as far south as the Neotropical boundary, and the whole of Greenland. 



Sub-regions. — Like all the other regions, the Nearctic is divided into 

 four sub-regions, which are as follows: — (1) Calif ornian ; (2) Rocky 

 Mountain ; (3) Alleghany ; and (4) Canadian. The Californian Sub-region 

 consists of a narrow strip of country, west of the Sierra Nevada and the 

 Cascade range, and extending from Vancouver Island and part of British 

 Columbia in the north almost to latitude 30° in the south. The Rocky 

 Mountain Sub-region lies immediately to the east of the Californian, and 

 includes the whole of the dry and elevated area covered by the mountains 

 from which it takes its name. To the south it embraces Lower California 

 and the Central Mexican plateau, while its eastern boundary begins on the 

 coast a little to the north of the Rio Grande, runs up nearly due north to 

 about the 50th parallel, then sweeps round to the north-west almost to the 

 Little Slave Lake, thence southwards to near the source of the Missouri 

 River, and finally westwards till it meets the boundary of the Californian 

 Sub-region. The Alleghany Sub-region comprises the United States east 

 of the last sub-region and south of the Great Lakes, and includes Nova 

 Scotia. All the remaining portion of North America and Greenland con- 

 stitute the great Canadian Sub-region. 



Physical Features. — The Nearctic Region presents a great variety of 

 physical features. Like the Palsearctic Region, it extends from beyond the 

 Arctic Circle to the Northern Tropic, and hence has a great range of 

 temperature. In the northern portion the winter temperature is much 

 lower than is found at a corresponding latitude in Europe, and this is 

 largely due to the great widening out of the land mass towards the Polar 

 Regions. Add to this the extreme contraction of the area in its sub- 

 tropical portion, and we have two principal reasons for the somewhat 

 smaller variety in the forms of animal life as compared with the Palsearctic 

 Region. The chief physical features of the region are the large lakes and 

 inland seas in the north-eastern portion and the important ranges of 

 mountains in the west. The latter run from north to south, and are 

 practically a continuation of the great chain which runs through Central 

 America and the west of South America. In the east are smaller ranges, 

 constituting the so-called Appalachian Highland, while in the centre of this 

 great continent is a vast extent of plain, which in the north is frozen and 

 barren, between latitudes 50° and 60° covered with forest, and in the south 

 dry, treeless desert. Greenland, the outlying portion of the Nearctic 

 Region, is entirely arctic, and buried beneath a mass of ice of unknown 

 thickness. 



Zoological Characteristics. — The close affinity of the Nearctic fauna with 

 that of the Palsearctic Region has already been pointed out (see p. 5). 

 The number of families of terrestrial Vertebrates represented in the Nearctic 

 Region is 120, namely, 26 of Mammals, 59 of Birds, 21 of Reptiles, and 14 

 of Amphibians. This number is considerably below the corresponding one 

 for the Palsearctic Region, but, on the other hand, while there are no- 

 peculiar families in the latter, the Nearctic Region possesses five, namely, 

 the Haplodontidse (Sewellels) and Antilocapridse (Prongbuck) among 

 Mammals ; the Chamseidse (Wren-Tits) among Birds ; the Aniellidse among 

 Reptiles, and the Sirenidse (Mud-Eels) among Amphibians. 



There are, besides, several peculiar genera of importance, of which 

 Scalops (Web-footed Moles), Taxidea (American Badger), Haplocerus (Rocky 

 Mountain Goat), and Ovibos (Musk Ox) may be taken as examples. The 

 latter, however, was once a Palsearctic species, and occurred even in Britain. 

 The American Bison (Bison bison), Grizzly Bear (Ursus horribilis), 

 American Beaver (Castor canadensis), Wapiti Deer (Cervus canadensis), 

 Moose (Alces americana), and the Caribou (Rangifer caribou) are also 

 characteristic animals, while the families Geomyidse (Pocket Gophers) and 

 Heteromyidse (Pocket Mice) cfec. among Mammals; the Tetraonidse (Grouse) 

 and Meleagridse (Turkeys) among Birds ; the Xantusiidse among Reptiles ; 

 and the Desmognathidse among Amphibians, are more numerously repre- 

 sented in this region than elsewhere. 



Californian Sub-region. — In this small area are found representatives 

 of 86 families of terrestrial Vertebrates, as follows : Mammals, 21 ; Birds, 

 49; Reptiles, 8, and Amphibians, 8. The Californian is the only one 

 of the Nearctic Sub-regions which possesses any families peculiar to itself. 

 These are three in number, namely, the Haplodontidse (Sewellels), Chamseidse 

 (Wren-Tits), and Aniellidse- (a family of Lizards). Of characteristic families, 

 though not peculiar, the Phyllostomatidse (Vampire Bats) and Noctilionidse 

 (Free-tailed Bats) should be mentioned, while the genera Netirotrichus 

 (Mole-Shrews) and Bassariscus (Cacomistles) are also to be placed in this 

 category. 



Rocky Mountain Sub-region. — This sub-region is the richest portion 

 of the Nearctic Region, for it possesses representatives of 107 (out of 120) 

 families of terrestrial Vertebrates. This number is made up as follows : 

 Mammals, 25 ; Birds, 55 ; Reptiles, 18 ; and Amphibians, 9. Although there 

 are no peculiar families in this area, yet there are several very characteristic 

 genera, among which may be mentioned Antilocapra (the Prongbuck), 

 Haplocems (the Rocky Mountain Goat), Bison (the American Bison), and 

 Cynomys (Prairie Dogs). The families Dicolylidse (Peccaries), Dasypodidse 

 (Armadilloes), Cotingidse (Chatterers), Trogonidse (Trogons), and Cracidse 

 (Curassows) are examples of essentially Neotropical families which just 

 enter this sub-region from the south, while, lastly, the Helodermatidse 

 (Poisonous Lizards) are common to this area and the Mexican Sub-region. 



Alleghany Sub-region. — The Eastern United States, forming this Sub- 

 region, are to be regarded as the most characteristic portion of the 

 Nearctic Region. Some 99 families of terrestrial Vertebrates are repre- 

 sented, as follows : Mammals, 18 ; Bitds, 53 ; Reptiles, 16; and Amphibians, 

 12. No family is peculiar, and among Mammals there is only one genus 

 that is confined to the Sub-region, namely, CondyVura, (Star-nosed Mole). 

 The Didelphidse (Opossums) are common to this and the Rocky Mountain 

 Sub-regions, while the extreme south of Florida is the home of many 

 typically Neotropical groups of animals. Examples of such may be found 

 in the Phyllostomatidse (Vampire Bats) ; Coerebidse (Honey-Creepers) ; 

 Aramidse (Courlans) ; the Frogs of the family Cystignathidse ; the Land- 

 Shells of the family Urocoptidse ; and the Butterflies of the family Heli- 

 conidse. The most interesting of the peculiar Birds are the celebrated 

 Passenger Pigeon (Ectopiistes migratorius) and the Carolina Parrot (Conuropsis 

 carolinensis) — both on the verge of extinction — while other characteristic 

 groups are the Meleagridse (Turkeys), and Sirenidse (Mud-Eels). 



Canadian Sub-region. — In this sub-region only 75 families of terres- 

 trial Vertebrates are represented, namely, 20 of Mammals, 44 of Birds, 

 3 of Reptiles, and 8 of Amphibians. It is thus the poorest section of the 

 Nearctic Region, but at the same time an interesting feature of the fauna 

 is presented by the number of genera and species which are common to 

 it and the Palsearctic Region. Among these may be mentioned Cervus 

 (Deer), Rangifer (Reindeer), Alces (Elk), Bison (Bison), Ovis (Sheep), Gulo- 

 (Gluttons), Mustela (Martens), Lemmus (Lemmings), Ursus maritimus (the 

 Polar Bear), Vnlpes lagopns (the Arctic Fox), and many birds. The genus 

 Ovibos (Musk Ox) is now peculiar to the sub-region. The Reptiles and 

 Amphibians are few, and of little importance. Lastly, certain genera of 

 Butterflies, such as Parnassius, Colias, Ccenonympha, CEneis, and others, 

 are well represented and characteristic. 



Number of Families of terrestrial Vertebrates in the Nearctic 

 Eegion and its Four Sub-regions. 



Nearctio Region in General ... 



Californian Sub-region 

 Kocky Mountain ,, 

 Alleghany ,, 



Canadian 



Mammals. 



Birds. 



Reptiles. 



Amphibians. 



26 (2) ' 



59(1) 



21(1) 



14(1) 



21(1) 



49(1) 



8(1) 



8 



25 



55 



18 



9 



18 



53 



16 



12 



20 



44 



3 



8 



Total. 



120 (5) 



86(3) 

 107 

 99 



75 



1 The figures in parentheses indicate the number of peculiar families. 



INSULAR FAUNAS. 



The animal life on islands is of special interest to the student of 

 zoogeography. As a rule the genera and species are much fewer in number 

 than is the case in continental areas, but at the same time these are often 

 remarkably peculiar and well defined. Before a detailed study of any 



