CLASSIFICATION IN LITHOLOGY. — GENERAL CONCLUSIONS. 59 



clatiire is found, from its structure and composition, to come under either 

 melaphyr or diabase, its label would be written as follows, according as it 

 was one or the other : — 



Basalt, Melaphyr, Diorite. 

 Basalt, Diabase, Diorite. 



But if this diorite belonged apparently to the basaltic species, but could 

 not be referred to either the melaphyr or diabase variety, its label would be 

 thus : Basalt, Diorite. 



When the names are trivial, or when they are not properly variety or 

 sub-variety names of the species under which the specimen is placed, the 

 label is written as follows : Basalt, Diabase (Calc-Diabase). For the frag- 

 mental forms it is written, Basalt, Tufa ; or Basalt, Porodite ; or Basalt, Dia- 

 base, Porodite — as the case may be. 



The variety and sub-variety names are not here considered essential, but 

 are employed out of deference to the common custom. However, in order 

 to make the work symmetrical, such names, and even new ones, have been 

 introduced, where it seemed necessary ; but all can be dropped or contiuued, 

 and expanded as the advance of the science may require. 



The special nomenclature and its applications will be given in the descrip- 

 tive portion of the work, with the account of the specimens, and to that the 

 reader is referred. If, in course of time, a system of nomenclature like 

 that employed in botany and zoiilogy, should be desired, the system em- 

 ployed here would readily furnish it, by dropping the commas between 

 the specific name and its variety and sub-variety, with the Latinization of 

 these names. The names would then be in their proper order, and afford 

 us both binomial and trinomial names, as the case might be. 



