78 NEW PALEOZOIC VEKTEBRATA. [Feb. 5, 



Sagenodus reticulatus Newberry, Geol. Sur. of Illinois, iv, 1870, 

 p. 349, PI- ni, Fig. 9. 



PL I, Figs. 2, 3. 



I refer four scales to this species ; one of them differing some- 

 what from the other three, a difference which may be due to differ- 

 ence of position. The characters in which all agree, are the very 

 elongate form, with medium to large size, and the coarse and rather 

 homogeneous tesselation, in which the areas partake of the elongate 

 form of the scale. The distal border is narrowly rounded and is 

 marked by a border of fine longitudinal striae, which are not inter- 

 rupted by concentric lines or reticulations. The single scale 

 referred to has a lobe of the distal margin which projects beyond 

 the remaining portion, but which has the sculpture identical with 

 that of the latter. The proximal end is rounded in all and is 

 marked in two of the scales by a few coarse radii. Three of them 

 are further characterized by the presence of an oblique groove 

 near one of the long margins. In two of them this groove cuts off 

 a lanceolate area, passing from one long margin to the distal bor- 

 der, which is unsymmetrical by reason of its presence ; in the scale 

 above mentioned very much so. The center is near the proximal 

 extremity, and is not conspicuously marked. It is possible that the 

 grooved scales belong to the lateral line, but if so, the latter must 

 be very irregular. The diversity in the grooves leads me to suspect, 

 however, that all of them do not belong to the lateral line. This 

 is a large species. 



Measurements. mm. 



T^. XT ^ • 1 X (vertical 10 



Diameters No. i (groove incomplete) -, , . ,. , ^ 

 ^^ ^ ^ (longitudinal . 36 



Four tesserse transversely measured in. ... , 3 



T-.. XT ^ I . , (vertical 14 



Diameters No. 2 (complete with groove) \y . ,• , 



Three tesserae (transversely measured) in 2 



Nos. F. 175, 176; 57, 58; F. 55, 56; F. 59, 60; Lacoe collec- 

 tion. 



Prof. Newberry, at the place above cited, includes in this species 

 two scales of different form from those here described, and from 

 the one which he represents at Fig. 9. I should have preferred to 

 have retained his name for the species, to which these two scales 



