GEN. CLUPEA. TWAITE SHAD. 175 



there being a notch or emargination in the upper 

 jaw, not observed in the former; in other respects 

 the generic characters are the same. We have two 

 British species. 



(Sp. 144.) A.finta. Twaite Shad. This fish 

 may be readily distinguished from the other native 

 species, with which it has been often confounded, by 

 its distinct teeth on the upper jaw, and a row of 

 dark spots along each side of the body. It is a fish 

 of some size, measuring from ten inches to upwards 

 of seventeen inches ; and is named in some places 

 Mother of the Herrings, and in Scotland, according 

 to Dr. Parnell, Rock Herring. It is a migratory 

 species, ascending large rivers in numerous troops 

 in the month of May, or earlier, and there . deposit- 

 ing its spawn, retiring to the sea about the end of 

 July. In the Thames, however, which this fish 

 has long frequented in great numbers, the spawning 

 season is not till the second week in July. The fry, 

 which, as already mentioned, were long confounded 

 with the Whitebait, always bear a series of lateral 

 spots above the median line, and present various 

 other marks of distinction. A comparative view of 

 the two will be found in the fourth volume of the 

 Zoological Journal, PI. V. The food of the Twaite 

 Shad consists chiefly of the small Crustacea which 

 form the staple subsistence of the Clupeidse, but it 

 does not abstain altogether from small individuals of 

 its own class. Although of small repute for the 

 table, the flesh being coarse, dry, and insipid, these 

 fishes are caught in great numbers in many places 



