H. Stanley Jevotis — Nomenclature of Igneous Rocks. 309 



become for our purpose essentially the same, and the name vesicular 

 may be used for both. 



Table II. List of Contractions for Names of Structures. 



Name Contraction Name Contraction 



Allotriomorphic-granular Allotrio- 



Eutaxitic Eutaxo- 



Felsophyric (see Microfelsitic) Mifelso- 



Olassy or vitreous Vitri- 



Hyalopilitic Hyapilo- 



Hypidiomorphic-granular Hypidio- 



Intersertal Inserto- 



Miarolitic Miaro- 



Microfelsitic Mifelso- 

 Micropegmatitic or Granophyric Mipegmo 



Microspherulitic MispherO' 



Ocellar Ocello- 



Ophitic Ophito- 



Panidiomorphic -granular Panidio- 

 Pilotaxitic Pitaxo- 



Poecilitic Poecilo- 



Porphyritic Porpho- 



Rhomboidal (Rhomben-)|Tji r i 



felspar structure 



Spherulitic Sphero- 



Tr achy tic Tracho- 



Variolitic Varilo- 



Vesicular Vesico- 



Vitrophyric (see Glassy) Vitri- 



There remain a few miscellaneous contractions which are 

 occasionally employed, and may be conveniently exhibited in 

 another table. The prefixes for ' rich in soda ' and ' rich in 

 potash ' are obtained by contracting the German words natron and 

 kali, rather than the English words soda and potash, because, owing 

 to their use for symbols in chemistry, the former are more widely 

 understood in England than are the latter in Germany. 



Table III. List of Miscellaneous Contractions. 

 Before a Consonant Before a Vowel Meaning 



VII. Family-Names. 



For the sake of further illustration, I have prepared, and 

 reproduced below, a table showing the classification of the Alkaline 

 Series of plutonic igneous rocks, which gives both the old and the 

 new names (see Table IV, p. 312). The Alkaline Series is troubled 

 with a particular superabundance of names. Probably this is 

 because most of its members have been discovered in recent years, 

 since detailed petrographical research became general, and its families 

 have therefore actually become subdivided to a far greater extent 

 than those of the Calc-alkaline Series, although the latter has been 

 studied very much longer. The table therefore shows that a great 

 number of names will become redundant, if a systematic nomen- 

 clature be adopted. 



Hitherto nothing has been said respecting the names of families. 

 This is because complete revolution is impossible, and existing 



