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genus it has recently been placed in a separate 

 family, the Matonineae, of which it is the sole living 

 representative. The restricted geographical range of 

 Matonia, considered in connexion witli the clearly 

 marked peculiarities in structure and form, leads us 

 to expect other evidence in support of the natural 

 inference that the genus is a survivor of a once 

 more vigorous and widely spread family. If Matonia 

 were a recently evolved type which has not spread 

 far from its original home, we should expect it to 

 conform more closely than it does to other ferns in 

 the Malay region. Even assuming for the sake of 

 argument that variation may occur per saltnm, and 

 new forms may be produced differing in more than 

 the finer shades of small variation from their parents, 

 the peculiar features of Matonia are too pronounced 

 and its individual characteristics too obvious to 

 warrant the assumption of recent production. It is, 

 hoAvever, from the testimony of the rocks that we 

 obtain confirmation of the opinion that these Malayan 

 species are plants on the verge of extinction. In 

 shales of Jurassic age exposed on the Yorkshire coast 

 at Gristhorpe Bay and in iron-stained rocks of the 

 same age between Whitby and Scarborough, well 

 preserved leaves have been found agreeing in the 

 shape of the fi-ond, as also in the form of the leaflets 

 and of the groups of sporangia which they bare, with 

 those of Matonia pectinata. 



