258 PALEONTOLOGY OF NEW-YOEK. 



311. 2. OLENUS UNDULOSTRIATUS (m. *;?.)• 



Pl. LXVII. Figs. 3 a, b. 

 Compare Olemis spinulosus, Dalman. 



Buckler semielliptical or sublunate, the posterior angles extended into diverging spines ; 

 eyes lunate ; glabella (apparently not lobate) marked by fine rugae ; facial suture extending 

 from the margin of the cephalic shield, in front of the eye, to the base of the same, distant 

 from the angles ; articulations slender, those of the lateral lobes grooved. 



The single fragment figured, is all that has been seen of this species. The character of 

 the buckler, form of the eye, and direction of the facial suture, induce me to refer it to 

 the Genus Olenus. It is, in many respects, analogous to the preceding species, but is too 

 obscure to decide whether the glabella is lobed or not. The segments of the thorax are 

 imperfect, and the extremities are not preserved. 



Fig. 3 a. The fragment, natural size. 



Fig. 3 A. A part of the same enlarged, showing the course of the facial suture, and the rugose striated 



glabella. 



Position and locality. This specimen was obtained at Snakehill, Saratoga lake, in the 

 soft olive shales, associated with other species belonging to this group. {State Collection.) 



312. 1. AGNOSTUS LOBATUS (n. sp.), 



Pl. LXVII. Figs. 5 a -/. 



Minute, trilobate, with a narrow border around the base and sides ; middle lobe often 

 with a small tubercle near its larger extremity. 



This species bears considerable analogy to the Swedish specimens from a similar geo- 

 logical position, but they are not identical. Our species is always smaller, and I have never 

 seen the small node or tubercle at the base of the central lobe; but it presents a similar 

 character on the other extremity. All our specimens have the appearance of the caudal 

 shield of a small trilobite, and two or three individuals are apparently articulated. 



Figs. 5 a, b. Individuals of the natural size. 5 c, d. The same magnified. 

 Figs. 5 e, /. Specimens sliowing an articulation of the lobes. 



Position and, locality. This pecidiar little fossil has been found only in some calcareous 

 beds, intercalated with the shales of this group, one mile east of Troy. I am indebted to 

 Dr. Skilton of that city for good specimens of the same. (State Collection.) 



