40 CONTRIBUTIONS TO NORTH AMERICAN ICHTHYOLOGY - IV. 



Our knowledge of the American species has been in a state of great 

 <.. illusion until very lately, tlie first careful comparison of the species 

 having been made by Mr. Carman in 1874. On his excellent paper* the 

 following account is based. (Raia or J\'j<t, the Latin name of fishes of 

 this genus.) 



1. Atlantic Species. 



\ 



i iiitlim- nf the disk anterior to the spiracles rounded, not formiug an angle at the 



tip of the snout. 

 t Rows of teeth about 58. 



48. K. <>riiiacea Mitcliill. Common Skate; Litilr NA-rt/c; Tobacco-box. 



Form rhomboid, with all the angles rounded; spines largest on the 

 anterior extensions of the pectorals, where they are close-set, strong, 

 laterally compressed and hooked backwards; smaller ones are scattered 

 over the head, above the spiracles, above and in front of the eyes, on 

 the back, the median line of "which is comparatively smooth, without 

 larger median series, except in the young. A triangular patch on the 

 shoulder-girdle: inner posterior angles of the pectorals nearly smooth ; 

 in the males near the exterior angles of the pectorals are t\vo rows of 

 iai -e erectile hooks, pointing backwards. Females with groups of small 

 .scale.s (iii each side of the vent ; teeth small, the middle ones sharp in 

 the males; all blunt in the females; jaws much curved; each side of tail 

 with a dermal fold; caudal tins rough, not separate to the base. Color 

 li.ulit brown, with small round spots of dark brown; females larger than 

 the males. L. 1 to L* feet (G firman.) The smallest and commonest of our 

 skates; abundant on our coast, especially northward. 



l.'.nn ,,;,,, I,-,, i Mill-hill, Am. .Imini. Sci. Arts, xi, 290, l-.Ti: Ra'm ii/lniitcrla Giinther, 

 siii. 1C.-J: Caiman. 1. -. 17(1. i 



Bowa ..r i.-rii, gg i^ t,. ; 



l?>. 1C. << 4-M:il;i Mih -bill. n,-<ll,tl,;l /,',(//; Jii,/ 



ieneral form and appearance of the preceding: the arrangement of 

 spine* similar, except that additional rows of spines are present down 

 the back and along the sides of the tail; caudal lin not separate, rough 

 with small .spines; jaws curved. Color light brown, with rounded dark 

 spis ; a translucent .sp;i<-e on each side of the snout ; near the posterior 

 an^le of the pectoral there is usually ,l>nl not always) a large white 

 on -II n.s. with a dark spot in t he cent re and a darker border; two smaller 

 .similar .spots often present ((inrnnui). Six.e very much larger than the 



' (in i In Skated i l,':ij:i-i i.r tin- KaM.-ni Coasts of tin- United States : Uy S. W. (iai- 

 nian. ProC. I'-.-i. BOC. Nat. Hist. xvii. Nnv. t, 1~71. pp. 170-181. 



