20 



Fishery Board for Scotland. 



bone), whicli marks the beginning of tbe scales on the nape of the 

 neck, is taken for the point. 



Fig. f). — Measuring Board. 



I j! "" '' Nfiil»ii»ij>— — 



Fig. 6. — Travelling T-square. 



XVIII. The top of the opercular cleft. A pin is put into the 

 cleft in its extreme anterior upper angle. The pin is then the point 

 for the measurement. 



XIX. Hindmost point of the bony edge of the gill-cover. A piece 

 of paper placed under the edge helps to define it. 



XX. The articulation of the first ray of the pectoral fin. A pin 

 inserted into the articulation is the point. 



XXI. Beginning of the dorsal fin. The membrane uniting the 

 first two rays from the third is cut. The two first rays are raised 

 into a vertical position. A cut is then made in the dorsal edge of the 

 body by sliding a knife down the front edge of the first ray. A pin 

 inserted into the cut constitutes the point. 



XXII. End of the dorsal fin. A pin is inserted into the dorsal 

 edge of the body immediately behind and close to the base of the last 

 ray. 



XXIII. Articulation of the first ray of the ventral fin. The 

 point is marked by a pin inserted into the articulation. 



XXIV. Beginning of the anal fin. The point is marked in a 

 manner similar to that in XXI. 



XXV. End of the anal fin. A pin is inserted in the dorsal edge 

 of the body immediately behind and close to the base of the last ray. 



XXVI. Beginning of the dorsal ramus of the tail fin. If the dorsal 

 edge of the body in front of the beginning of the dorsal ramus be 

 scraped free of scales, a little cartilaginous ray-like body is seen in 

 the skin. The anterior point of this body is marked by a cut into 



