510 SILURIAN TRILOBITES OF NEW SOUTH WALES, vi. 



Fig. 4. — A complete individual, except for the absence of tail, showing the 

 genal horns reaching beyond the tail; ( x y-; about). (Coll. Mitchell). 



Fig, 5, — A very fine fragment showing twenty-one somites on the thorax; 

 ( X V-; about). (Coll. Mitchell). 



Staurocephalu,^ mnrchi.^oni Barr. 



Fig. 6. — Cephalon of a mature specimen, showing the ornamentation dis- 

 tinctly; ( X f ). (Coll. Mitchell). 



Fig. 7. — Cephalon and thorax. Cephalon incomplete. (Coll. Mitchell). 



Fig.8. — Thorax and pygidium, showing structural features verj' clearlj'; 

 (enlarged). (Coll. Mitchell). 



Fig. 9. — Cephalon nearly perfect, showing ornamentation of the frontal 

 lobe of the glabella; (slightly enlarged). (Coll. Mitchell). 



Fig. 10. — A drawing of the specimen represented in figure 9; (much en- 

 larged). (Coll. Mitchell). 



Fig. 11. — A nearly perfect specimen; (much enlarged). (Coll. Mitchell). 

 Calymene duni E. & M. 



Fig. 12. — A nearly perfect pygidium, showing the bifurcate distal end of 

 the pleural ribs, etc. (Coll. Geological and Mining Museum, Dept. 

 of Mines, Sj^dney). 



Staurocephalus murchi^oni Barr. 



Fig. 13. — Almost perfect specimen; (slightly enlarged). Fig. 11 is an 

 enlarged drawdng. 



Bounyonyia boivningensis E. & M. 



Fig. 14. — A photo, in which the features are intensified and restored. 

 (Photos by C. Glutton and J. Mitchell). 



