Maryland Geological Survey 361 



general evenly convex. Basal surface convex, swelling to median longi- 

 tudinal axis moderately. Transverse median sutures curve at first slightly 

 convex back till posterior are quite convex. Vertical diameter of median 

 teeth about five in horizontal diameter, their surfaces with usually distinct 

 transverse or vertical wrinkles or nearly smooth. Length (width) 

 59 mm."— Fowler, 1911. 



This species is recorded from the Monmouth and later Upper Cre- 

 taceous formations in the New Jersey area. Only uncertainly-determined 

 fragments represent it in the Maryland Cretaceous. 



Occurrence. — Monmouth Formation. Brooks estate near Seat 

 Pleasant, Prince George's County. 



Collection. — Maryland Geological Survey. 



ARTHROPODA 



Class CRUSTACEA 1 

 Order DECAPODA 



Family ASTACIDAE 

 Genus HOLOPARIA McCoy 

 The following species are referred to this genus with due reserve, as 

 until the cephalothorax is known their exact position in the Astacoid 

 series must remain doubtful. The specific characters of the fossils, how- 

 ever, may be readily appreciated ; and the definition of the species may call 

 attention to the matter and lead someone to search for the missing parts. 



Holoparia gabbi Pilsbry 

 Plate X, Figs. 1-4, 8, 9 



Holoparia gabbi Pilsbry, 1901, Proc. Acad. Nat. Sci., Phila., p. 115, pi. i. 



figs. 11-14. 

 Holoparia gabbi Pilsbry, 1907, in Weller, Geol. Survey of New Jersey, Pal:. 



vol. iv, p. 846, pi. ex, figs. 12-15. 



1 Former descriptions by the author have been revised in terminology and 

 slightly changed in phrasing for this report, but only type material has been 

 used in such revision. Information upon additional specimens is given in 

 separate paragraphs. 



