TRANSACTIONS OF SECTION C. i'2i 



G. On Some Limericl Traps. Bij W. W. Watts, M.A., F.G.S. 

 fCommwnicated by permission of the Director-General of the Geologica) Survey.] 



After referring; to previous descriptions of these Carboniferous volcanic rocks bv 

 Messrs. Hull and Kinahan tbe writer gave a short account of their succession and. 

 mineral characters. The earliest eruptions were of porphyrite lava and ash, 

 followed after an interval of sedimentation by eruptions of basaltic lava and ash. 

 Intrusive masses of porphyrite and quartz-porphj-rite penetrate the Old Red Sand- 

 stone, Carboniferous Limestone, and the eruptive masses themselves. The latest 

 lava in the area is a limburgite containing large crystals of augite and pSeii- 

 domorphs of olivine in a fine-grained base consisting of augite and magnetite. 



