REVUE SUISSE DE ZOOLOGIE 

 Tome 75, n° 44 — Décembre 1968 



813 



Relationship between 

 body length and body weight 



of Stenella styx Gray 

 and Delphinus delphis Linné 

 from the Western Mediterranean 



By 



Margarete GIHR and Georg PILLERI 



Brain Anatomy Institute Waldau/ Berne (Switzerland) 



With 1 Figure and 1 Plate. 



During two expéditions in the Western Mediterranean in the summers of 

 1966 and 1967, 24 Delphinus delphis L. (17 <J and 6 $, 1 subadult çj spécimen, 

 Plate I, A) and 12 Stenella styx Gray (5 ç? and 7 Ç, Plate I, B) were captured. 

 The body length (cm) and body weight (kg) of each individual were measured 

 immediately after harpooning; thèse values are set out in Table 1. 



Schultz (1938) was the first to calculate the body weight of various Cetaceans 

 from body length, using the gênerai relationship 



W = F L" or in terms of logarithms log W = log F + (n) (log L). 



His spécimens were mainly comprised of foetuses and adult spécimens of the 

 Finback, foetuses and adult spécimens of the Blue Whale, and a few adult speci- 

 |mens of the Humpback, Gray, Sperm and Bottle-nosed Whale. He obtained a 

 relationship of W = 0.0000269 L 2 789 , where W = body weight in kg, L = body 

 length in cm. F is a function of the length and weight units and represents the 

 point of intersection of the straight line with the y axis, while n = factor deter- 

 mining the slope of the line. 



By substituting logarithms, Sergeant (1962) determined a length — weight 

 relationship of 



W = 0.000025 L 2 895 



