ABNORMALLY DEVELOPED THORNBACK 29 



ought to remark that Mr. Young has not, I believe, seen 

 Professor Steenstrup's paper, and thus his critical remarks 

 upon the specimen under his charge are the more valuable. 



In conclusion, I consider that only one deduction, as to 

 specific identity, can be drawn from the significant com- 

 bination of characters possessed by this Scottish Wolf-fish, 

 namely, that it is the AnarrJiidias minor of Eggert Olafsen 

 (" Reise i Island," 1772, p. 592) a new and interesting 

 addition to the British fauna. 



The Plate is an accurate reproduction in lithography of 

 a photograph taken of the fish when in the flesh. 



W. E. C. 



NOTE ON AN ABNORMALLY DEVELOPED 

 THORNBACK (RAIA CLAVATA, L.) 



By R. H. TRAQUAIR, M.D., F.R.S. 



Keeper of the Natural History Collections, Museum of Science and 



Art, Edinburgh. 



A FEW weeks ago Mr. Charles Muirhead presented to the 

 Museum of Science and Art a specimen of a Ray caught 

 thirty miles east of the Isle of May, which seemed to him to 

 be somewhat peculiar in its appearance. The form, colouring, 

 dermal armature, and dentition of this Ray (see Fig. i)show 

 clearly that it is a Thornback (Raia clavata, L.), though the 

 large thorns are not so abundant on it as we often see them 

 on other and more especially on larger specimens. The fish 

 is a female ; its entire length is 22^- inches, its greatest width 

 I 5 inches. In front and on each side of the snout there is an 

 angular notch which is deeper on the left than on the right 

 side, and consequently the anterior aspect of the fish appears 

 as if divided into three points, one median and two lateral. 



Of course it is evident at the first glance that this mal- 

 formation is conditioned by the non-adherence to the sides of the 

 head of the anterior extremities of the pectoral fins, which con- 

 sequently project freely on either side of the snout. A 

 similar; case, also in a Thornback, is figured by Day, " British 



