museum coi.lectio.xs. 745 



Life Histokt of Races. 



(1) Descent without modification — Lamp-shells, oysters. 



(2) Progress (models of parts) — Horse, salmon, shell-snails. 



(3) DiflEerence in Sexes — Size (in hawks), colour (in I'obins), form 

 (Huia crow). 



Geographical DisxraBUTiON and Migration. 



A series of cases, illustrating the geographical distribution of 

 animals, forms a fascinating study. It may be a salmon or a trout, 

 a fox or a rabbit, that interests us. A study of their distribution will 

 be found to be economically profitable. Man is the pnncipal agent in 

 the distribution of certain animals. His parasites are being trans- 

 planted into eveiy habitable part of the globe. A large amount of 

 material is necessaiy to form a perfect collection, so that gaps might 

 be temporarily filled by sketches or photographs. Small distribution 

 maps should be well in e^'idence, the areas of distribution being 

 coloured red— 



i. Temperature is a strong governing factor in distribution — 



e.g., goats, whose presence practically defines the altitude. 



The earth, but for mountains, would probably be arranged, 



zoographically, in zones. 



ii. Barriei-s to migration and emigration (Australia) — 



(a) The desert extending from the west coast of Australia to 



Central Australia ; 

 (&) Bass Straits. 



iii. Difference of faunas. Faunas of — 



{a) Continent and island — e.g., Australia and Lord Howe 

 Island ; 



(h) Continental and Oceanic Island — e.g., Tasmania and 

 Kerguelen Island. 



(c) Two adjacent islands — e.g., Bali and Lombok. 



{d) Nearest continent and anomalous island — e.g., Australia 

 and New Zealand. 



4. Distribution — 



(«) Contmuous — Cats (Felis), Silver Eyes (Zosterops). 



{b) Discontinuous — Platypus, lung fishes. 



(c) Local- — Marsupial mole, hehneted honey-eater (Ptilotis 

 cassidix). ' .^ 



{d^) Of an order — Marsupialia. *«#«" Tr"'*^^. 



{d^) Of a ia.xm\j—PiUidce (Ant Thrushes). ;€^ V^'^ '^'^- 



(d^) Of a genus — Acanthodrilus (Earth WormW'C5^> - ,* 



(d^) Of a species — Pycnoptilus (Pilot Bird). '^ ^ 



(e) From a common centre of origin. 



(e') Galaxias. 



(e^) Casuarius. 



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