Buenos Aires (Fowler 1926); and Mar del Plata, 

 Argentina (Berg 1895; MACN 5151; MSNG 27472). 

 Sarda sarda extends further north and south in 

 the eastern than in the western Atlantic, from 

 near Oslo, Norway to Port Elizabeth, South Africa. 

 In Scandinavia it has been taken in Oslo Fjord 

 (Collett 1879a; five ZMO specimens, 425-600 mm 

 FL) and along the Swedish and Danish coasts of 

 the Kattegat (Smitt 1892; Jensen 1937; Loven 

 1938; Jensen 1941; Otterstr^m 1943). There is one 

 record from the Netherlands (Hubrecht 1879; 

 Redeke 1941) and there are records from Scotland 

 (Montrose on the east coast, Rae and Pirie 1968; 

 Wigtown on the west coast, Rae and Pirie 1969) 

 and from many counties in Ireland (Farran 1923; 

 Went 1968, 1969, 1971; Wheeler and Blacker 1969, 

 1972). It is common throughout most of the Medi^ 

 terranean (Belloc 1954) including the Adriatic Sea 

 (Brunnich 1768; Ninni 1882; goljan 1963), Aegean 

 Sea, Sea of Marmora, and the Black Sea (Pallas 

 1811; Athanassopoulos 1934; Niimann 1955; Demir 

 1963, 1964; Banarescu 1964; Svetovidov 1964; 

 MNHN A. 6870; USNM 199648; BMNH 

 1864.4.25.13, 1888.2.3.53). There are records from 

 the four major groups of islands off Europe and 

 Africa: the Azores (Hilgendorf 1888; Collins 1954; 

 USNM skeletons), Madeira (Lowe 1850; BMNH 

 uncat.). Canaries (Valenciennes 1844; Stein- 

 dachner 1865, 1868; Vinciguerra 1893), and Cape 

 Verdes (Cuvier and Valenciennes 1831; Dumeril 

 1858; Cadenat 1950; Postel 1950). Along the coast 

 of North Africa, there are records from Spanish 

 Morocco (Lozano Cabo 1970), Morocco (Dollfus 

 1955); Spanish West Africa (Mather and Day 

 1954); Port Etienne and d'Arguin Bank, Mauri- 

 tania (Chabanaud and Monod 1927; De Groot and 

 Nijssen 1971); Cape Verde, Senegal (Rochebrune 

 1882; Pellegrin 1908; Cadenat 1937; Frade and 

 Postel 1955). Sarda sarda is also present in the 

 Gulf of Guinea from Senegal to Ghana (Irvine 

 1947; BMNH 1939.7.12.31; Jensen 1967; 23 USNM 

 specimens from the Guinean Trawling Survey; 

 Williams 1968); along the coasts of Angola (Osorio 

 1890) and South-West Africa (Molteno 1948) 

 through the "Cape Seas" (Barnard 1927) to the 

 Cape of Good Hope (Smith 1949), Mosselbaai 

 (Molteno 1948), and Port Elizabeth, South Africa 

 (SAM uncat.), in the southwestern corner of the 

 Indian Ocean. 



Geographic Variation.— For purposes of com- 

 parison, Sarda sarda was divided into five 

 populations: North America, South America (no 



vertebral counts available), northeast Atlantic 

 (Scandinavia, Atlantic Europe, and the Azores), 

 Mediterranean Sea (including the Black and 

 Adriatic seas), and Gulf of Guinea (extending 

 south to South Africa). Comparison of meristic 

 characters shows that the two western Atlantic 

 populations are similar to each other as are the 

 Mediterranean and Gulf of Guinea populations. 

 There are differences in a number of characters 

 between combined eastern and combined western 

 Atlantic populations, mostly correlated with 

 higher vertebral counts in the eastern Atlantic. 

 The small northeast Atlantic sample is similar to 

 the other two eastern Atlantic populations but 

 resembles the western Atlantic populations in 

 some characters. 



The North American population has 50-53 ver- 

 tebrae, mode 51, x 51.1, compared to a range of 

 52-55, mode 53, x 53.3, for the Mediterranean-Gulf 

 of Guinea (Table 9). Three specimens from the 

 Azores have 51 vertebrae, thus resembling the 

 western Atlantic population. Correlated with ver- 

 tebral counts, there are fewer fin rays in the west- 

 ern Atlantic (Tables 10-12): dorsal spines modally 

 21 vs. 22; second dorsal rays modally 16 vs. 17; total 

 second dorsal elements 24 vs. 25; anal rays modally 

 15 vs. 15 or 16; total anal elements modally 22 

 skewed toward 21 vs. 22 or 23 skewed toward 22. 

 Independently, there are also fewer gill rakers 

 (Table 7) in the western Atlantic (North America 

 modally 17, x 17.6, South America modally 18, x 

 18.7) compared to the eastern Atlantic (Medi- 

 terranean and Gulf of Guinea, x 20.9) 



Based on admittedly small samples, there seems 

 to be a difference between western and eastern 

 Atlantic specimens of S. sarda in the size of the 

 caecal mass. Western Atlantic specimens have the 

 caecal mass extending posteriorly for more than 

 half the length of the body cavity in ventral view; 

 eastern Atlantic specimens less than half this dis- 

 tance. 



Study material was adequate to compare three 

 areas morphometrically: western Atlantic, Medi- 

 terranean Sea, and Gulf of Guinea. There appear 

 to be differences in three characters (Table 21). 

 The western Atlantic population has a lower 

 second dorsal fin (68-90 thousandths of fork length, 

 X 80) and a smaller caudal spread (204-235, x 222) 

 than do the two eastern Atlantic populations 

 (85-117, X 95 and 81-99, x 91 for the second dorsal 

 height of the Mediterranean and Gulf of Guinea 

 populations, respectively; 226-270, x 247 and 

 223-289, X 253 for the caudal spread). In the snout- 



611 



