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THE POPULAR SCIENCE MONTHLY. 



hand, the front teeth, of the Notoryctes are small, hardly more 

 than pegs, and leave a considerable gap on the median line, a 

 disposition like that observed in some of the edentates. It might 

 be well to compare this dentition with that of the Myrmecobia, 

 which is also Australian, and with that of some of the types of 

 Eocene fossil mammals which have recently been discovered in 



Fig. 4. — Notoetctes. (View of the under side ; two thirds the natural size.) 



South America. The angular apophysis of the lower jaw is 

 markedly bent within, a tolerably constant characteristic of the 

 opossums. The marsupial bones, on the other hand, are but lit- 

 tle developed. They are represented only by two small osseous 

 nodules diverging forward and united in the tendon of the oblique 

 external muscle of the abdomen at its insertion on the symphysis of 

 the pubis. They are hardly visible with the lens, and might easily 

 pass undetected in a hasty or superficial dissection. Nothing is yet 

 known of the method of reproduction of the Notoryctes. 



As a whole, we are struck by the resemblances exhibited be- 

 tween the Notoryctes and the African Chrysochlores ; the forms 

 of the skull, of the molar teeth, and of the fore limb are such as 

 to lead us to suppose something more than a simple secondary 

 adaptation depending on an identical mode of life. The unlike- 

 ness, on the contrary, between the incisors and the canine teeth 

 of the two types is deserving of closer study. It is of interest 

 to recollect that these two genera are not the only ones which 

 establish by their outer forms a bond of relationship between the 

 South African and the Australian fauna. The Pedetes (Helamy), 

 or great jerboa of the Cape, exhibits absolutely the forms of the 

 Australian kangaroos, although it is a placentary rodent. There 

 are also well-known relations between the South African and the 

 Australian flora. — Translated for The Popidar Science Monthly 

 from La Nature. 



[Mr. J. Douglas Ogilby has reached the conclusion, after a careful study of Mr. Stir- 

 ling's accounts of this animal, that in it we have at last obtained a definite connecting link 

 between the Monotremes (Ormihorhi/ncus) and the Marsupials (kangaroos and opossums). 

 At the present state of our knowledge it would, he thinks, be presumptuous to class Noto- 

 ryctes among the Monotremes proper, although several naturalists incline to the opinion 

 that its affinities are closer to those animals than to the Marsupials. — Ed. P. S. M.] 



