368 Systematic Paleontology 



dactylus is decidedly longer than the pollex. The natural mold is also 

 preserved though not perfect. The description is from the type specimen. 



Occurrence. — Mataavan Formation. Ulmstead Point, Magothy 

 Kiver, Anne Arundel County. Monmouth Formation. Brooks estate 

 near Seat Pleasant, and railroad cut west of Seat Pleasant, Prince 

 George's County. 



Collections. — Maryland Geological Survey, Academy of Natural 

 Sciences of Philadelphia, New Jersey Geological Survey, Wagner Free 

 Institute of Science. 



Callianassa conradi var. punctimanus n. var. 

 Plate XI, Figs. 4, 5 



Description. — The manus is about equally convex on both sides, as in 

 C. conradi; sides acute and crenulated, the proximal margin outside very 

 little contracted to the articulation. A longitudinal series of six punc- 

 tures runs to the base of the dactylus, and another of fewer punctures to 

 base of the pollex. The pollex is broken, but at the base it is triangular in 

 section and found like that of C. conradi. 



Length of hand 16.4 mm. ; breadth 13 mm. ; thickness 6 mm. 



Type Locality. — Head of Bohemia Creek, Delaware. 



It differs from C. conradi chiefly in the more numerous punctures of the 

 back of the head. None of the New Jersey individuals of C. conradi shows 

 so many punctures. 



Occurrence. — Monmouth Formation. Head of Bohemia Creek, Dela- 

 ware; Brooks estate near Seat Pleasant, Prince George's County, Mary- 

 land. 



Collection. — Maryland Geological Survey. 



Callianassa clarki n. sp. 



Plate XI, Figs. 6-8 



Description. — The manus is somewhat more convex on its outer face; 



the lateral edges are pinched into acute, beautifully crenulated keels. The 



pollex has a low rounded median tooth on the grasping face, thereby differ- 



