PLATE II. 



Carboniferous Trilobites. 

 Pkillipsia Colei, M'Coy. 1844. (P. IG.) 



Pig. 1. — A small and rather mutilated specimen, wanting the clieek or 

 portion of the head and some of the thoracic somites. The eye on the left side is well 

 preserved. Magnified six times natural size. 



Pig. 2. — A larger and more perfect specimen ; the genal portion of the head is not 

 preserved clearly, and the eyes are wanting. Magnified twice natural size. 



Pig, 3. — Another example, wanting the lateral portion of the head and the eyes ; the 

 thoracic segments on one side are very well preserved. Magnified three times natural 

 size. 



Pig. 4. — This specimen is preserved as an intaglio only, but shows the glabella, the 

 thoracic somites, and the pygidium united. Magnified three times natural size. 



Pig. 5. — A very complete caudal shield or pygidium. Magnified twice natural size. 



Pig. 6. — A detached hypostome. Magnified four times. 



All the above specimens are from the Museum of the Geological Sm-vey of Ireland, 

 Dublin, and were obtained from the black Carboniferous Shale, occurring in rocks in a 

 stream opposite Plax Mill, north-east of Ballintra and Carrickbreeny, Donegal, Ireland. 



Pig. 7. — Phillipsia Colei, M'Coy. Restored outline, three times enlarged. 



Pig. 8. — Outline of glabella, y. Cheek, c, separated to show the suture. 



Pig. 9 «, b. — One of the thoracic ribs drawn in outline, seen from above, and in 

 profile. 



Pig. 10. — The pygidium, drawn in outline. 



