1874.] 181 [Burbank. 



This is the largest species of skate on this coast ; on account of 

 its great size it is called the Barndoor Skate by the fishermen. The 

 angles in the outline of Icevis are more acute than in either of the 

 preceding. Its muzzle is much produced. The rostral cartilage is 

 long, wide, and flattened on the upper and under surfaces; its sides 

 are about parallel ; near the end it tapers above and below in such a 

 way as to form a shovel or chisel. The spines of the rostrum are 

 worn smooth, both on the upper and under sides of the snout, as if it 

 was used as a spade in the mud and sand. The spines of the entire 

 body are very few and small. There are some above the eyes and 

 spiracles, on the snout, along the anterior borders of the pectorals, 

 and on the back. Those on the back are often so small as to be per- 

 ceived only by rubbing the finger over the skin. A median dorsal 

 row extends from the posterior portion of the back to the second 

 caudal fin. These are larger, laterally compressed, and slightly 

 hooked. Two lateral rows extend along the sides of the tail, imme- 

 diately above the membrane ; these are either straight or hook for- 

 ward; their points are directed horizontally. 



The caudals are separated by an interspace with spines. The tail 

 extends some distance beyond the posterior fin. On this extension 

 there is usually a false or membranous fin ; it possesses no rays, and is 

 wholly unlike the caudals in structure. It is this membrane that has 

 led naturalists to describe the species as having three caudals. 



Lcevis is subject to great variations in color. Examples from the 

 same locality present marked differences in this respect. Commonly 

 it is brown, clouded, marbled, or spotted with lighter ; occasionally 

 the spots are ringed with darker. A couple of specimens in this col- 

 lection have kidney-shaped marks near the shoulders. The hooks on 

 the pectorals of the male are common to all the species of the genus 

 inhabiting our waters. 



Size of a male from Massachusetts Bay: L. 42, 14, 231. W. 32. 

 Teeth f§; width of tooth bearing surface on the jaw 3| inches. 



The spines on a female from the same locality were much more 

 numerous. Size, L. 47-i, 15|, 25. W. 34|. Teeth §1, more blunt 

 than those of the male. 



Mr. L. S. Burbank described and exhibited specimens from 

 a granitic vein in Athol, Muss., which he had recently dis- 

 covered. 



This vein is of the same general character as that of the noted 

 beryl locality of South Royalston. It is, however, of much greater 



