Fishes of the Western North Atlantic 419 



ranean. It is represented in the tropical-subtropical waters of the eastern and western Indo- 

 Pacific by a form {S. lewini Griffith, 1834) closely resembling diplana in form of head 

 (including arrangement of mucous pores) and in the shape and relative position of the fins. 

 We have not been able to find any significant differences between small specimens from 

 Panama, southern California, Hawaiian Islands or Celebes^" and the Atlantic series of 

 comparable sizes listed above (p. 415). However, since Whitley^' describes the teeth of 

 the Australian lewini as becoming "finely denticulated" with growth, which is not the case 

 in the Atlantic diplana, it seems wise to retain both specific names, awaiting a comparison 

 of adult specimens. 



Occurrence in the Atlantic. Diplana was separated from zygaena so recently that very 

 few reports of it have yet appeared under its own name. Information as to its occurrence 

 in the eastern Atlantic is confined to the facts that Valenciennes^* described his malleus^ 

 which his illustration shows to be the head of diplana, as Mediterranean and Atlantic; 

 that Springer" reports a head of diplana from tropical West Africa (Gold G)ast) ; that the 

 collection of the British Museum contains specimens apparently of this species in addition 

 to zygaena from the Mediterranean ; and that there is a specimen of it labelled "Europe" 

 in the collection of the Harvard Museum of Comparative Zoology. Locality records that 

 can be referred with certainty to diplana in the western Atlantic are Rio Grande do Sul, 

 Rio de Janeiro and probably Pernambuco, Brazil, Colon, both coasts of Florida, South 

 and North Carolina, and a station about 90 miles off Cape May, New Jersey. These are 

 enough to show that its range closely parallels that of zygaena. It is so common off south- 

 eastern Florida that we have recently received a report of 1 9 adult males taken there in a 

 single day. It appears not to range as far north along the United States coast during sum- 

 mer as zygaena does. Similarly it is possible that its range may not extend as far to the 

 south in the southern hemisphere, although information of its presence is so scant for the 

 South American coast as to preclude any definite statement in this regard. Neither is any 

 information available as to its abundance relative to that of zygaena anywhere off the 

 American Coast. 



Synonyms and References: 



Shark, no name, Marcgrave, Hist. Nat. Brazil, 1648: frontispiece (this is the earliest illustration that we have 



found of a Hammerhead with head of the diflana shape). 

 Le Marteau (in part), Duhamel, Traite Gen. Peches, (2) j (9), 1777: 303, pi. 21, fig. 3—7 (ill., apparently 



this species) ; Broussonet, Mem. Acad. Roy. (1780), 1784: 66l (by ref. to Duhamel, 1 777, as above). 

 Zygaena malleus (in part) Valenciennes, Mem. Mus. Hist. nat. Paris, 9, 1822: 223, pi. 11, fig. I (descr., ill. 



of head, Medit., Atlant., but apparently confused with his own tudes, because teeth descr. as denticulate) ; 



Risso, Hist. Nat. Europ. merid., j, 1826: 125 (part, by ref. to Valenciennes, 1822); Storer, Mem. Amer. 



Acad. Arts Sci., N. S. 2, 1846: 508 {malleus Valenciennes, 1822, incl. in synon.) ; Giinther, Cat. Fish. 



Brit. Mus., 8, 1870: 381 (OTa//e«/x Valenciennes, incl. in synon.); Day, Fish. Gt. Brit., 2, 1880-1884: 



294 (ot<j//^«x Valenciennes, incl. in synon.), pi. 154 (ident. by shape of head, no loc.) ; Doderlein, Man. 



12. Specimens in the collection of Harvard Museum of Comparative Zoology, 480 to 740 mm. long. 



13. Fish. Aust., /, 1941: 121. 14. Mem. Mus. Hist. nat. Paris, p, 1822: 213. 

 15. Proc. Fla. Acad. Sci., 5, 1941 : 49. 



