154 NEW YORK STATE MUSEUM 



indicated has altered I observed and made note of a 

 cephalon on the anterior limb of which was a very pro- 

 nounced elongate and spatulate extension, as is represented 

 in outline in our figure. This was so fragile that I was un- 

 able to preserve it and no other specimen of the cephalon was 

 complete in this frontal region. It is such a prolongation or snout 

 as one sees in Salter's figure of D. longicaudatus [British 

 Trilobites, 1864^ pi. 3, fig. 19] from the Wenlock shale which one 

 may regard as an incipient condition of the Probolium condition. 

 Lower Devonic. St Alban beds, Griffon Cove river, P. Q. 



Dalmanites coxius nov. 



This species is represented by a pygidium subequally triangular 

 and distinctly fiat with relatively narrow axis and broad sides. 

 The margins have a slight outward curve and meet behind in a 

 short broad caudal spine. The pleural ribs extend very nearly to 



Dalmanites coxius 



the margin and on the cast they appear to be elevated abruptly 

 on the posterior edge and slope gradually from this edge upward. 

 The same character is noticeable on the segments of the axis. The 

 intervening grooves are thus not sharply defined except at their 

 upper margins. There are 12 of these flattened shelving ribs on 

 the pleura and 12 to 15 on the axis. Each of the pleural ribs shows 

 trace of a fine surface groove. The test is very thin and its sur- 

 face so far as known very finely granulated. The specimen has 

 a length of 35 mm and a width of 44 mm. I should be at a loss 

 for a known species with which to compare this tail. In respect 

 to the character of its segments and its thin test it is like D. 



