658 GEOLOGICAL SURVEY OF NEW JERSEY. 



separate gill openings on each side ; the young are toothless and have 

 rudimentary eyes. 



AMMOCCBTBS, Dum. 

 Maxillary tooth single ; lingual teeth not pectinated. 



A. appendix, De K. {Ichthyomyzon, Grd.) Lamprey. 



Brown, tinged with blue ; fins pale amber ; one large double 

 tooth in lower side of mouth ; dorsal fin begins in front of mid- 

 dle of body ; vent near posterior third of body, with conspicu- 

 ous " appendix " in males in spring. Streams of Southern New 

 England and New York, representing A. niger, small black 

 lamprey, of region west of Alleghanies (length, 6 to 10 inches), 

 which, however, is distinguished by having dorsal fin start 

 further back. 



" This small species is very abundant in the majority of our 

 creeks that communicate directly with the rivers. It is very 

 similar in all its habits to the lamper eel." 



PBTROMYZON, L. 



Maxillary teeth two or three ; lingual teeth pectinate. 

 P. marinus, L. {americanus, Le S.) Great Sea Lam pre}'. 



Head scarcely longer than gill region ; numerous teeth on 

 large buccal disk, arranged in oblique series; color olive brown, 

 mottled with blackish patches ; dull brownish below. Length, 

 24 to 36 inches. Enters streams in spring, to spawn. 



" This species is quite common in spring along our coast, enter- 

 ing the bays and rivers. It is valued as an article of food, and 

 many are taken and oiFered for sale in our fish-markets." 



P. marinuB, var. nigricans, Le S. Lamper Eel. Large Black Lamprey. 

 Head one-third longer than " chest ; " color plain bluish black 

 above, pale below. Length, 12 inches. Usually described from 

 a distinct variety (dorsatus) found in Cayuga Lake, New York, 

 which has head a little longer and a fleshy ridge on back in front 

 of fin. Our nigricans is supposed to be the young of the pre- 

 ceding species. 



"An allied species that is found wherever the previous one is 

 met with." 



