Asterolepis omata, vav. australit 



Plate XXI. 



Fig. 5.— Restored diagrammatic outline of sutures and sensory 

 canals in Phlyctaenaspis awtralis, var. eonfertituber- 

 culata, based on the described specimen. 



Fig. 6. — Phlyctaenaspis acadica, Whiteaves sp. Cranial shield; for 

 comparison with Australian examples. Lower Devonian. 

 Campbelltown, Canada. Specimen in the National! 

 Museum coll. Cir. nat. size. 



