242 PALEONTOLOGY OF NEW JERSEY. 



ing on the sides of tlie anterior end to the point of greatest diameter, and 

 also extending backward beyond the mesial sulcus in considerable breadth, 

 apparentlv reaching nearly or quite to the posterior extremity of the valves 

 Anterior dorsal plates coml)ined apparently of only medium size, quadran- 

 gular or lozenge-shaped, and pointed at either extremity, placed with their 

 longest diameters in the direction of the junction of the valves. No pos- 

 terior dorsal plates appear to have existed. Posterior dorsal slope concave, 

 leaving the hinge-line sharply elevated. 



The specimen being entirely an internal cast tlie surface characters 

 of the shell can only be approximately determined. As no other species, so 

 far as I can ascertain, is known from this formation in America, I can draw 

 no conq^arison. 



Fonnation and locality. — In the upper layers of the Upper Green Marls 

 at Shark River, New Jersey. Collected by Dr. Kneiskern. Collection at 

 Rutgers College. 



TERIDID^. 



Genus TEREDO Liuu, 



Teredo emacerata, n. sp. 



Plate XXX, Fig. 25. 



The species is known only by the casts of tubes, which are slender and 

 not known to exceed two inches in length. They are closely crowded in 

 the only exanqiles observed, and have been found in burrows in wood. 

 Their direction is much contorted, and although often nearly thi-ee-six- 

 teentlis of an inch in diameter at the lower extremity, they rapidly taper to 

 within one-half of that size, and are very slender for the greater part of their 

 length. The lower extremity is rounded, and in some cases bulbous. The 

 species differs from T. tibialis Mort. of the middle beds, in having burrowed 

 in wood instead of in sand, and in being much smaller, much more tortu- 

 ous, and more densely crowded than is usual with that species, besides 

 having no appearance of having formed a shelly lining. 



Formation and locality. — In the upper layer of the Upper Marl, at 

 Shark River, New Jersey. 



