PALEONTOLOGIC CONTRIBUTIONS 79 



We have referred this species to Phragmoceras. The term 

 Phragmoceras has been used rather loosely for breviconic, curved 

 compressed shells with contracted apertures and protracted hypo- 

 nomic sinus. The genus as restricted by Hyatt comprises, how- 

 ever, only species with an undivided brachial aperture. That our 

 species possessed such a one, is shown by the specimen reproduced 

 in plate 26, figure 3. 



While plate XXVI, figure 1, is to be considered as the holotype 

 of the species, we figure with this species several fragments of 

 smaller specimens from the type locality. One, plate XXVI, figure 

 4, may well be a younger individual of that form, from the shape 

 of the living chamber. Corresponding to its growth stage the 

 aperture is still wide open. Plate XXVI, figures 2 and 5, are two 

 septa showing the sections at the corresponding growth stages and 

 the position of the siphuncle; the last figured specimen retains a 

 segment of the siphuncle which is nummuloidal. There are still 

 other specimens indicating that this species is common enough 

 in the waterlime beds of Litchfield to be considered as having been 

 an associate of the eurypterids in the fauna of the Bertie water- 

 lime sea, as indicated by the specific name given this interesting 

 form. 



Hexameroceras microstoma nov. 



Plate 27, figures 2-9 



Description. Conch a small arcuate brevicone; transverse 

 section broadly oval with little difference (one-tenth) in major and 

 minor diameters ; greatest width nine-tenths of the thickness and 

 situated halfway between dorsal and ventral sides or slightly 

 toward dorsal side ; siphuncle ventral, submarginal. 



Living chamber long for a Hexameroceras (about six-sevenths 

 of thickness), strongly curved on dorsal side, with less convex 

 margin on inner, ventral side. Aperture but slightly sloping from 

 brachial area to hyponomic area. Lateral sinuses of brachial area 

 decreasing in size from first to third; third pair very small. Hypo- 

 nomic area consisting of narrow slit, occupying about half of 

 aperture and oval ventral opening whose edges project spoutlike. 



Camerae shallow, depth about one-tenth of greatest width. 

 Sutures fairly straight transverse, with a low, narrow saddle on 

 the ventral side and a broad, low saddle on the dorsal side. Septa 

 shallow, their depth about equaling that of the camerae. 



The surface sculpture has not been observed. 



Measurements. Largest (a gerontic) specimen (living chamber 

 and six chambers) measures 39.5 mm in length, its living chamber 



