32 2 Memoir Sears Foundation for Marine Research 



of Beaufort, North Carolina, they were absent from extensive collections made by 

 Hildebrand and his associates with gear of various types, though adults were taken 

 in the estuaries there in winter and early spring. 



In short, Hickory Shad probably spawn in the spring, but it remains to be 

 learned whether they spawn in fresh or salt water. However this may be, to the north 

 of New York they are the most plentiful during autumn. 



Food. Hickory Shad feed chiefly on small fish of various kinds. Their fish diet 

 is supplemented by squid, small crabs, various small crustaceans, and by fish eggs 



{59- 84). 



Enemies and Parasites. Little is known about the enemies of this species; but no 



doubt they are eaten by larger fish and are caught in limited quantities by man. Linton 



(55: 438) found individuals parasitized with nematodes {Ascaris sp.), cestodes (larval 



Scolex polymorphus), and trematodes (Distomum appendiculatum). Wilson (136: 12) found 



the Hickory Shad to be a host of the copepod Lernanthropus brevoortiae. 



Relationships. Though closely related to P. chrysochloris, Hickory Shad have a 

 heavier and less shapely (less streamlined) body; the depth in adults is greater than 

 the length of the head (measured from margin of upper jaw); in chrysochloris, exclusive 

 of very large or very fat specimens, the depth is equal to or less than the head. In 

 mediocris the shield of scales on the dorsal fin base consists of more than one row of 

 scales anteriorly and extends nearly or quite to the last ray of the fin, whereas in chryso- 

 chloris it is composed of only one row of scales throughout and is missing on the last 

 four or five rays. The scales on the side of the Hickory Shad have a pronounced crenulate 

 membranous border preceded by longitudinal striations, while in chrysochloris the 

 border is only slightly irregular and the striations not evident. In mediocris there is 

 only a slight ridge above the base of the pectoral, which ends at the tip of the axillary 

 process; in chrysochloris a more pronounced depression (pocket) is provided for the 

 pectoral fin, and the more prominent ridge above its base extends well beyond the 

 axillary process of the pectoral. 



In large Hickory Shad, 300 mm and upward, teeth in the upper jaw are missing, 

 but in specimens at least up to 150 mm long they are present there; however, those 

 in the lower jaw persist, though very small; the patch on the tongue is very small, and 

 the teeth minute. In chrysochloris the teeth are consistently larger, persist in the upper 

 jaw among adults, are large in the lower jaw, and the patch on the tongue is notably 

 larger. Although the proportions and counts overlap, it is evident that Hickory Shad 

 have a proportionately deeper body, deeper caudal peduncle, more anal rays, and 

 fewer gill rakers than P. chrysochloris. 



There are differences in color also, evident in preserved as well as fresh examples. 

 Hickory Shad have a large dark spot behind the upper part of the opercle, often 

 followed by several smaller dark spots, and the adults frequently have dark lines along 

 the rows of scales on the upper part of the side. In P. chrysochloris these markings are 

 missing, and the dark blue or grayish color of the back ends very abruptly, not tending 

 to shade into the silvery color of the side, as in Hickory Shad. 



