3 64 Memoir Sears Foundation for Marine Research 



tyrannus of similar size, greatly reduced on back and at base of caudal ; 5 or 6 vertical 

 rows of scales exposed between tip of pectoral and base of pelvic fin. A row of large 

 modified scales on each side of median line in advance of dorsal. Ventral scutes 

 moderate, 18—20 in advance of pelvic fins and 12—14 behind them. 



Head small, 3.3-3.85 in SL, its depth 3.6-3.8. Snout with a definite median 

 notch, its length 3.9-4.6 in head. Eye small, 4.7-5.4. Interorbital 4.1-4.7. Cheek 

 notably deeper than long. Maxillary rather short, reaching about to vertical from 

 posterior margin of pupil, 2.2—2.4 i" head. Mandible short and included, its upper 

 margin (within mouth) nearly straight, its length to joint 1.8-1.9 in head. Upper 

 section of Opercle with prominent radiating ridges. Gill rakers long, and numer- 

 ous, the longest ones about as long as snout and half of eye, about 115— 125 on 

 lower limb. 



Dorsal fin low, its longest rays scarcely longer than the snout, its origin nearer 

 to margin of snout than to base of caudal by a distance nearly equal to diameter of 

 eye; its base with a low sheath composed for the most part of a single series of 

 scales, not extending above the basal third of the rays. Caudal fin very short, the 

 middle rays about as long as eye; lower lobe somewhat longer than upper one, more or 

 less damaged, but shorter than head, about 3.7-4.4 in SL. Anal very low, its origin 

 under, or a little behind, vertical from tip of last dorsal ray, its base 5.25—5.7 in SL; 

 a very narrow sheath of scales at base. Pelvic fin small, with a gently convex margin, 

 its outermost ray not much longer than innermost ray; the fin inserted about under 

 origin of dorsal; the length 3.4-3.6 in head. Pectoral fin very short, not falcate, its 

 length 7.25-8.25 in SL, or 1.8-2.2 in head, its longest ray about three times longer 

 than the shortest one, failing to reach base of pelvic by a distance notably greater than 

 diameter of eye. Axillary appendage of pectoral short and broad, only a little more 

 than half of length of fin, 3.0-3.8 in head. 



Color. Old preserved specimens dark greenish on back and upper part of side. 

 Lower parts silvery to brassy. Sides of head silvery. A roundish dark spot at shoulder, 

 about the size of pupil of eye ; only one specimen at hand with suggestions of auxiliary 

 dark spots on side behind shoulder spot. Fins all uniform brownish. 



Relationship. It is strange that no additional specimens like the ones herein de- 

 scribed, collected in 1874, are among the many in the U. S. National Museum from 

 the general vicinity of Long Island and northward to Woods Hole, Massachusetts. 

 These specimens differ in so many respects from the more or less typical B. tyrannus 

 in the same general vicinity (Noank, Conn.) that it seems necessary to recognize them 

 as representing a distinct species. The apparent distinctions are shown in a comparison 

 with specimens of B. tyrannus of equal size from the same general vicinity of Noank 

 (p. 365). It is evident from this comparison that brevicaudata is not a geographical variant. 



The eight specimens in the Study Material are, in part at least, those studied by 

 Goode, who gave measurements of two specimens from USNM 14846 and an accu- 

 rate description (^^: 33, 37); although he gave them the "variety" name brevicaudata., 

 he did not designate a type. Therefore Goode's variety has been elevated to specific 



