PLATE 9. 



iLLrSTEATITE OF Me. KljSfABlAN's PaPER " 0^r GrAJVITIC XSJ) OTHER 



Ik'sej^ite Rocks." 

 Vide Proceedings E. I. Acad., Yol. 2, Ser. 2, p. 102. 



A. Diagrammatic sketcli of a dolerjrte dyke, seeming one rock, but of 



different textures in different parts- — a and h, clay or shale 

 partings ; c and d caugM up pieces of schist. In the vicinity 

 of the parting b, the rock is amygdaloidal, while the division 

 of the dyke on the left of that parting has a rude horizontal 

 columnar structure combined in places with a spheroidal 

 structure. The arm to the left has a rude columnar structure. — 

 Cleggan. 



B. Diagrammatic sketch of a doloryte dyke in felsite-schist, showing 



a platy and spheroidal structure. — Mannic Bay. 



C. Sketch-map of part of a dyke of felstone in granite. In the whole 



of the felstone is a structure oblique to the walls of the dyke, 

 while in part are lines nearly perpendicular to the others, 

 giving the rock a tesselated aspect. — Lough Bola. 



D. j^odular or conglomeritic-gneiss, changing into granitoid-gneiss. — 



Derrycemlagh. 



E. Angular pieces of schistoid- granite in intrusive oligoclasic-granite. — 



Omey Island. 



F. Section of conglomiretic-schist. — Ardadeny. 



G. Sketch-map of a small rock exposure, showing scaled old joint- 



lines in a homblende-aphanyte. — Letterdife. 



H. Sketch-map of a small rock exposure, showing some of the old 

 joint-hues scaled, while others are still open, but a small thick- 

 ness of rock alongside is indurated, and when the rock is 

 weathered stands up in a ridge. — Glan. 



I. Sketch-map of a small exposui-e of mieaceous-hornblende-rock, 

 showing the pitted surface caused by the weathering out of the 

 small bunches of mica plates. — Knockadai. 



J. Sketch-map of a weathered surface of a micaceous-hornblende-rock 

 containing large flakes of silveiy-white mica, the weathered 

 edges of the latter ha-^ing a peculiar angular arrangement. — 

 Mannin Bav. 



