l62 NEW YORK STATE MUSEUM 



connected with the articulation of the valves, but standing apart 

 with a well defined space between, indicating that they are a broad 

 chondrophore. Further material will be necessary to elucidate the 

 nature of this shell. 



It is clear however, from the list given, even though generic deter- 

 minations only seem safe at present, that this congeries represents 

 a stage of late Siluric, clearly older than the fauna of the Perce 

 rock, probably older than the beds of Cap Barre, but not necessarily 

 older than the north flank of the Mt Joli massive. These beds, the 

 highest in the series, lie lowest as the entire mass is slightly over- 

 turned. Working southward over the remaining exposures in 

 exceedingly rainy and cheerless weather, it is probable that we have 

 overlooked much that will throw light on' the relations of the series. 



Beyond the light, seaward of the road, on the edges of the escarp- 

 ment in the field whence the purer layers of limestone have been 

 removed for burning, and which appertain to the lower and southern- 

 most part of the series here represented, after careful search fossils 

 were found, not in the blue and more abundant limestone, but in thin 

 clinking limestone plates. 



The mode of preservation here is singularly favorable were the 

 material sufficiently abundant, the fossils being weathered out on the 

 surfaces of the plates and doubtless the fauna will prove an interest- 

 ing and instructive one under more favorable opportunities for 

 exploration. These slabs have afforded : 



Spicules of hexactinellid sponges Whitfieldella cf. bisulcata a 



Platyostoma Orthothetes (small) ■ 



Many crinoid stems and an occasional crushed head with ornamented 

 plates resembling Glyptocrinus. 



Calymmene (small species) Phacops of P. logani type 



Bumastus (small species) Phacops sp. 



Taking up for more minute consideration the trilobites, the time 

 values of whose structure is best understood, we may note 



I The common species of Phacops is fully developed, with glabellar 

 lobes fused by almost entire disappearance of the furrows, eyes ^ 

 rather small, cheeks rounded with the faintest trace, if any, of the 

 genal spinules indicating early age, and the doublure of the cephalon 



