GILUERT AND STARKS — FISHES OF PANAMA BAY 9 



This species is known as yet onl}' from the Biiy of Panixma. Like G. calif or- 

 niciiH, from whicli it difTcirs widely in other respects, it has the young attached to the 

 oviduct by a placenta. The three specimens obtained by this expedition are all 

 females; one of them contains well developed young. 



4. Galeocerdo tigrinus Miiller <£• Ilenle. 



Recorded from Panama by Jordan and Eollman (1889, p. 179), their speci- 

 men having been collected by the "Albatross." The species was not seen by the 

 authors. 



5. Carcharias aethalorus Jordan I- Gilhert. 



Abundant at Panama, where it is used as food though not highly prized. 

 Small specimens only were seen. In a male about 90 cm. long, the claspers are very 

 small, not reaching margin of ventrals. The teeth of both jaws are distinctly serrate 

 in these young examples, the sern? growing coarser towards base, equally present 

 on the two margins. The interspace between dorsals is 5 to 6 times base of 

 second dorsal (excluding the fleshy ridge before fin), and the base of anal consider- 

 ably less thiin (Ij in) its distance from caudal. In other respects the Panama 

 specimens answer well the original description. 



6. Carcharias velox (Gilbert). 



Plate I, Fii:. .3. 



Carcharinus velo.\\ Gilbert, Jordan & Evermann, iSgcS, p. 2747. 



Distinguishable from other known sharks of the Pacific coast of America lay the excessively 

 long, slender, acute snout, the slender body, and the very long caudal tin. 



Preoral portion of snout slightly more than if times width of mouth, 5 times distance 

 between nostrils, if times width of snout opposite outer angles of nostrils, \\ times interorbital 

 width, 24 times distance from chin to line joining angles of mouth. Nostrils transverse in position, 

 the inner angle nearer mouth than tij) of snout by a distance slightly less than lengt^^of nostril. PVont 

 of eye equidistant from nostril and front of mouth, the middle of eye nearer angle of mouth than 

 nostril; diameter of eye less than nostril, slightly more than half longest gill-slit. Snout very porous. 

 Folds at angle of mouth slightly longer than usual. liill-slits rather wide, the middle slit i| times 

 diameter of orbit. 



Teeth of lower jaw very narrow, erect, very minutely serrulate, appearing entire except with 

 the lens. The species thus represents a transition between Carcharias and the alleged genus 

 Hypoprion. Teeth in upper jaw very obliijue, wide at base, with a dee|) notch on outer margin, the 

 terminal cusp rather narrowly triangular. 



Pectoral broadly falcate, the anterior margin convex, the distal edge concave, both angles 

 rounded. Tip of i:)ectoral reaching a short distance beyond base of first dorsal. Anterior margin 

 of pectoral 2j times the posterior (inner) margin, about \\ times the distal edge. First dorsal 

 inserted about the diameter of orbit behind a vertical from axil of pectoral; nearer pectoral, therefore, 

 than ventral. The anterior margin is concave basally, convex on distal half, the anterior angle 

 rounded. The free margin is conca\e, largely owing to the much ]iroduced acute posterior lobe. 

 The vertical height e.xceeds the length of the base; the anterior Ujlje very high, extending beyond 

 tip of jx)Sterior when the fin is declined, equaling \ length of anterior margin of pectoral. Posterior 

 margin of first dorsal 3] in the anterior margin. Base of first dorsal contained 2\ times in interspace 



