PLATE I 



Fig. i. Bull sperm whale photographed from a helicopter south of 

 Terceira, 23 July 1956. (See Clarke, 19566) Note the dorsal fin, 

 and the unflexed, extended posture characteristic of a sperm whale 

 when loitering undisturbed at the surface. 



Fig. 2. The throat grooves, here comprising two deep grooves with 

 several accessory grooves (shown diagrammatically in text-fig. 3^, 

 p. 248). Note also the scratches caused by squids (seen most 

 clearly in the lower part of the picture), the white margin to the 

 upper jaw, and (on the left of the picture) the corrugations on the 

 surface of the chest. Whale F6, sperm J, i6-om., at Horta, 

 12 July 1949. 



Fig. 3. Stalked barnacles (Conchoderma attrition) parasitic on the front 

 teeth of whale SH67, sperm ,5, 15-5 m., on board Fl. F. Southern 

 Harvester, in 6o° 40' S, 8i° 24' E, 9 December 1947. 



Fig. 4. Foetal sperm whales from Horta. Above, g, 35-5 cm., 15 August 

 1951 ; below, 9, 24-1 cm., 25 July 1953. (See Table 3, p. 244, and 

 Table 5, p. 246.) Note the rudimentary form of the flukes, the 

 blowhole (in the lower picture), and the slight elevation of the 

 dorsal fin, which in the upper picture has been indented with 

 cord used in packing the specimen. Photo: P. M. David. 



Fig. 5. The dorsal fin (here pronounced), and six posterior dorsal 

 humps, of which the last (apparent as a dark spot on the ridge of 

 the tailstock in front of the insertion of the flukes) rises not abruptly 

 but smoothly, and so is not high-lighted in the picture. Whale 

 F18, sperm ?, 11-3 m., at Horta, 1 August 1949. 



Fig. 6. The mouth of a young sperm whale, showing the lower jaw 

 with teeth not yet erupted. Just visible are serial swellings which 

 mark the positions of unerupted teeth. Note also the half-white 

 pigmentation of the lower jaw. The 'blackskin' about the jaws has 

 been stripped for fishing bait (see Clarke, 1954a, p. 343). Whale 

 F17, sperm 3, 7-5 m., at Horta, 1 August 1949. 



Fig. 7. Maxillary teeth erupted close to the sockets which receive the 

 mandibular teeth. Detail from the palatal region of whale SH334, 

 sperm o, 16-9 m., on board Fl. F. Southern Harvester, in 63 26' S, 

 90° 00' E, 2 January 1948. 



