NO. 1395. CAMBRIAN BRACHIOPOD A— WALCOTT. 283 



ingly narrow or absent. Hinge line with two sharp, slightly projecting teeth near 

 the umbo [crura?]. 



Ventral valve with a narrow median ridge extending two thirds of the length of 

 the valve toward the front margin; also with a fainter ridge on each side diverging 

 toward the lateral third of the border of the valve; umbo very low; hinge area per- 

 ceptible but very narrow, longitudinally striated, and having a minute tooth on each 

 side of the very narrow and small foraminal opening. 



Surface ornamented with about forty or fifty line, faint, radiating strite; those of 

 the middle fifth are close, continuous, and straight; a few on each side of these are 

 more divergent, wliile those near the beak of the shell are fainter, closer than the 

 last, and moderately arched outward toward the lateral borders. The surface of the 

 valves is also marked by very fine but distinct concentric striae; and at somewhat 

 regular intervals by about twelve more distinct lines of growth. The concentric 

 stritB are usually as distinct as the radiating. Casts of the interior of the valves 

 exhibit a smooth surface with some irregular, sinous, radiating stri;e. 



Length 7 mm., width 11 mm. Length of hinge line, 8 mm. 



Observations. — Doctor Matthew kindly sent me the types and cotypes 

 of this species, and from them and collections in the United States 

 National Museum, sufficient data was obtained to clearly show that his 

 opinion that tlie species belong to Protorthls and not Kukm/inayf^^ 

 correct. As far as known the characters of the area, teeth and free 

 spondylium are the same as in P. InlllmjsL The smooth casts suggest 

 Kutorgma^' but the ribbed shells recall P. quacoensis and the area with 

 open delthyrium and free spondylium place the species in Protorthis. 

 Its Aery tine surface riljs diflerentiate P. latourensis from all other 

 described species. 



Format loth and locality.— 'MXA&Xo, Cambrian. St. John shales, divi- 

 sion Ic, Portland, New Brunswick. 



PROTORTHIS 'LIE.VIS, new species. 



Ventral valve transversely semicircular, moderately convex; surface 

 of cast smooth; area overhanging the hinge line at about 30° from the 

 plane of the margin of the valve. The cast shows a very clearly defined 

 free spondylimn. Shell about 6 mm. in width and 4 mm. in length. 



This is the only representative of the genus known outside of the 

 Atlantic basin Cambrian fauna. All other species occur in New 

 Brunswick and Cape Breton. Its smooth surface and inclined area 

 distinguish it from other species of the genus. 



Formation and locality. — Middle Cambrian. St. Croix sandstone, 

 one-half mile southeast of county court-house, Menominee, Wisconsin. 



PROTORTHIS NAUTES, new species. 



This species has the same type of punctate interior surface as P. 

 hillingsi, and casts of the exterior are marked by minute, closely set 

 papillffi that are casts of the punctfe in the shell. Traces of the shell 

 show the same type of papilla. It is highly probable that the shell 



a See figures 18-20, Pal. N. Y., VIII, Pt. 1, pi. iv. 



