624 CLASS XVII. 



t With head enormous, equalling in magnitude the third or fourth 

 part of the trunk. 



Balcena L. Transverse horny laminje adhering to the upper 

 jaw in place of teeth. Two spiracles distinct. 



The whales. The head is very large, making in some one-third of the 

 whole leng-th. These animals may be named toothless cetaceans, although 

 in the state of embryo (as Geoffeot Saint-Hilaire observed in Balcena 

 Mysticetus at the beginning of this century) teeth are present, which, from 

 the early ossification and coalescence of the groove in which they lie, do 

 not come to view, Ann. du Mus. x. pp. 364, 365. Eschricht afterwards 

 confirmed this observation in various species, so that it may be regarded as 

 a generally prevalent embryonal state. Unteraucliungen, s. 85 — 91. 



Compare on this genus J. A. Bennett Natiiurl. Historie en Natuurh. 

 Beschrijving der Walvisschen in the Natuurh. Verhandelingen van de Maat- 

 schappij der Wetensch. te Haarlem, 1809, v. i, with PL 



Sp. a) With back finless ; Balcena Mysticetus L., Schreber Sdugeth. 

 Tab. 332, Lacep. Ciitac. PI. i. fig. i, both from Marten's SpUzbergisclie 

 oder Groenldndische Reise-Beschreibung, Hamburg, 1675, 4to, Taf. Q, fig. a, 

 ScoRESBT 1. 1. PI. 12, fig. I, copied in ScHREBER Sdugeth. 366, and Cuv. Ji. 

 Ani., ed. ill., Mammif. PI. 100, fig. i ; the Greenland lohale, common 

 whale, la Baleine franche. This species attains a length of 60', and has the 

 longest baleen, on each side more than 300 pieces. Its food consists of 

 medusffi, conchifers and molluscs, amongst which last especially of Clio 

 horealis (see above, i. p. 775) and Sjnrcttella arctica (i. p. 774). The whale 

 fishery attained the greatest extension since the beginning of the seven- 

 teenth century, after the discovery of the island Spitzbergen^. On this 

 subject may be consulted Zorgdrager's bloeijende oplcomst der Groenlandsche 

 visscherij, 2e druk. 's Gravenhage, 1727, 4to, Scouesby Account, &c. 2nd 

 Pt. and by the same Journal of a Voyage to the Northern Whale-fishery, 

 Edinb. 1823, Svo. Another species without dorsal fin occurs on the south 

 coast of Africa and in the South Pacific and also at Japan, Balcena australis 

 Desmoulins, Balcena cajyensis Gov. ; see Eech. sur les ossem. foss. V. i, p, 

 374, PI. 25, fig. I, 2, 5, 6, {cranium), Schlegel Faun. Jaiwn., Mamm. 

 Taf. 28, 29. (Probably here also belongs Blumenb. Abb. Naturh. Gegenst. 

 Svo, 91, from Hessel Gerard Descriptio geocjrccph. transitu^ supra terras 

 Americanas in Chinam), Diet, class. d'JIist. not. PI. 140, fig. 3 (comp. 

 Desm. ibid. II. 1822, p. 161). This species has a head of relatively 

 smaller size. On it affix themselves Balani (Tubicinella balcenarum, see 

 above i. p. 637), Coronula bcdcenaris and species of Cyamus, of which 

 animals no one has ever been observed on the Greenland whale. 



b) Adipose fin on the bach. Sub-genus Balcenoptera Lac. Belly marked 

 by longitudinal grooves. 



The fin-fishes (rorquals) are not on the whole objects of the regular 



1 In the memorable voyage of Jacob Heemskerk in 1596, when a part of the 

 company passed the winter in Nova Zambia. 



