2^2 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 5/ 



Saratoga Springs, Saratoga County.; (76a) in a railroad quarry, i 

 mile (1.6 km.) north of Saratoga Springs, Saratoga County; and in 

 arenaceous limestone, 2 miles (3.2 km.) south of Poughkeepsie, 

 Dutchess County ; all in New York. 



Genus PTYCHASPIS Hall 

 PTYCHASPIS SPECIOSUS Walcott 



Plate 43, figs. 16-19 



Ptychaspis speciosus Walcott, 1879, Thirty-second Ann. Rept. New York 

 State Museum, p. 131. (Species described as below.) 



Piychaspis speciosus Walcott, Lesley, 1889, Geo!. Surv. Pennsylvania, Rept. 

 P4, Dictionary of Fossils, Vol. 2, p. 830. (Text figure reproduced from 

 a drawing sent him by Walcott.) 



Glabella large, very convex, almost subcylindrical, width a little 

 less than the length, nearly straight in front, the lateral angles 

 rounded, sides straight and nearly parallel ; posterior glabellar fur- 

 row extending deeply and obliquely about one-third across the 

 glabella and connected by a straight transverse furrow ; the middle 

 glabellar furrow is less deeply impressed and extends across the 

 glabella subparallel to the posterior furrow ; the anterior furrow is 

 indicated by a very obscure line opposite the anterior angle of the 

 palpebral lobe. The occipital furrow is deeply impressed throughout 

 its length. The occipital ring is strong and prominent, but not ele- 

 vated above the general surface of the glabella. Dorsal furrow 

 deeply excavated at the sides and well defined in front. 



The facial suture, cutting the frontal margin on a line with the 

 outer edge of the palpebral lobe, curves slightly outward, and passes 

 directly to the anterior angle of the palpebral lobe ; curving around 

 this it passes obliquely outward to the margin of the posterior limb. 



Fixed cheeks of medium width ; the frontal limb is impressed with 

 a groove midway between the dorsal furrow and its anterior margin ; 

 the posterior limb is subtriangular, with a furrow extending from the 

 dorsal furrow to its lateral margin ; the palpebral lobe is large and 

 separated from the fixed cheeks by a deep sigmoid furrow. Surface 

 granulose with waving striae on the central portion of the fixed cheeks 

 opposite the palpebral lobes. 



This species is referred to the genus Ptychaspis from its strongly 

 furrowed subcylindrical glabella and the direction of the facial 

 suture. The largest specimen obtained of the head has a length of 

 12.5 mm., with a breadth of 13.7 mm. at the palpebral lobes. 



