456 THE JOURNAL OF GEOLOGY. 



the effusive rocks has created a disturbance in the melaphyre- 

 basalt group that can only be quieted by the ejection of one of 

 the members of the group, probably the melaphyres, from the 

 position it now occupies. When this is done it is probable that 

 the diabases will take the position thus left vacant, and the 

 plagioclase-augite rocks will be found to occupy these places 

 with respect to each other : the gabbros, the position of a deep 

 seated rock, the diabases that of the corresponding holocrystalline 

 effusive, and the basalt that of the hypocrystalline equivalent. 



W. S. Bayley. 



Waterville, Me., June I, 1893. 



