106 EVOLUTION THE RESULT OF CHEMICAL FORCES. 



As soon as marsupials became established in the animal king- 

 dom they branched off into the different lines of development, 

 the herbivorous, the insectivorous, the carnivorous, &c. There 

 are marsupials corresponding with nearly every kind of quadru- 

 ped that is described in our familiar books of natural history. 

 When it is considered that undoubtedly from one marsupial 

 species branched off all the various tribes of the pouched animals, 

 and from one placental species divided off all the numerous races 

 of our modern animals, it is certainly a most remarkable circum- 

 stance that they should so nearly agree in all their ramifications. 



The original and primitive species of both orders, as we have 

 often insisted, must have possessed the full complement of 

 structural bones, because derived species never gain, but are 

 almost always losing skeletal parts. Therefore we predicate a 

 a common stem for the two orders, and that all the branches of 

 each order descended from one individual or species of that 

 order. Still if any should claim that each species or genus of 

 the present order of mammalia had developed out of the corres- 

 ponding species or genus of the marsupial order, then we would 

 reply, that our point was gained without further argument ; for 

 it would be simply impossible that so many animals should inde- 

 pendently and simultaneously pass through the great change 

 from the marsupial to the placental organization, unless there 

 were an inherent and irresistible tendency in the race itself 

 toward that advancement ; and this is all we are contending for. 



' O 



The fact of this remarkable parallelism of species in the two 

 orders was brought before me in the most striking manner when 

 visiting recently the exceedingly interesting museums of Aus- 

 tralia, particularly that of Melbourne. There are to be seen in 

 those collections specimens of marsupial striped tigers and spot- 

 ted leopards, marsupial wombat and climbing bears, pouched 

 foxes, wolves, native cats, bandicoot rats, leaping rats and mice, 

 marsupial rabbits, beavers, weasels, woodchncks, porcupines, 

 phalanger squirrels and flying squirrels, ant-eaters, vulpine 

 opossums, prehensile tailed monkeys, and many others that 

 might be named. All these are of living species of marsupials, 

 found in the Australasian islands. But there have also been 



