562 



CERUMEN CETACEA. 



Feruasac, M. k Baron, If A. D'Orbigny, Mono- 

 graphic des Cephalopodes Acetabuliferes, folio, 

 Paris, 1835. This splendid work is published in 

 numbers, of which eleven have appeared. As yet 

 the letter-press extends only to the general intro- 

 duction. 



Broderip, (W. J. ) Observations on the animals 

 hitherto found in the shells of the genus Argonauta, 

 Zoological Journal, vol. iv. p. 57. 



Richard Owen, Memoir on the Pearly Nautilus 

 (Nautilus Pompilius, Linn.) 4to. 8 plates, 1832. 

 This work contains, besides the description of the 

 structure which characterizes the lower or Tetra- 

 branchiate order of the class, some additional par- 

 ticulars on the structure of the infundibulum, and 

 of the brain, and on the function of the superadded 

 branchial hearts, in the Dibranchiate order of 

 Cephalopods. Descriptive and illustrated Catalogue 

 of the Physiological Series in the Museum of the 

 Royal College of Surgeons, 4to. vol. iii. contains 

 an account of the organs of sight and hearing in 

 the Cephalopods, 1835. Description of a new genus 

 of Cephalopoda (Rossia). Appendix to Sir John 

 Ross's Voyage, 1835. Descriptions of some new 

 species ; and anatomical characters of the Orders, 

 Families, and Genera of the class Cephalopoda, 

 Proceedings of the Zoological Society, March, 1836. 



(Richard Owen.) 



CERUMEN, (Germ. Ohrenschmalz.) This 

 secretion, formed by the glands of the ex- 

 ternal ear, has been examined by Fourcroy 

 and Vauquelin, and more in detail by Ber- 

 zelius.* According to Vauquelin it consists 

 of 0-625 of a brown butyraceous oil, soluble 

 in alcohol, and 0-375 of an albuminous sub- 

 stance, containing a peculiar bitter extrac- 

 tive matter. Berzelius observes, that, when 

 first secreted, cerumen appears as a yellow 

 milky fluid, which gradually acquires a brown- 

 ish colour and viscid consistency. Digested 

 in ether it imparts to it fatty matter, which re- 

 mains when the ethereal solution is distilled off 

 water ; it has a soft consistence, is nearly co- 

 lourless, and contains stearin and elain sepa- 

 rable by alcohol ; it is easily saponified, and 

 the soap which it forms has a rank unpleasant 

 smell and taste; and when decomposed by mu- 

 riatic acid, the fatty acids separate in the form 

 of a white powder, which rises with difficulty 

 to the surface, and fuses at about 105*. The 

 portion which remains after the action of ether 

 imparts a yellow colour to alcohol, and on its 

 evaporation there remains a yellow-brown ex- 

 tractive matter, soluble in water, and leaving 

 after the evaporation of its aqueous solution a 

 yellow, transparent, and shining vamish, which 

 is viscid and inodorous, but intensely bitter; 

 when burned, it exhales a strong animal odour, 

 and leaves an ash of carbonate of potash and 

 carbonate of lime, without any trace of a chlo- 

 ride. It is completely precipitated from its 

 aqueous solution by neutral acetate of lead. 

 That part of cerumen which is not soluble in 

 alcohol yields to water a small proportion of 

 pale yellow matter, which, when obtained by 

 evaporation, has a piquante taste ; it is not 

 precipitable by salts of lead, corrosive subli- 

 mate, or infusion of galls, and contains no 

 traces of phosphoric or chlorine salts. The 

 residue of the cerumen, insoluble in water and 



* Lehrbuch dcr Thierchemie. 



alcohol, gelatinises in acetic acid, but is only 



partially dissolved by it; that which is taken 



up appears to be albumen; and the undis- 



solved portion is brown, viscid, and transpa- 



rent; digested in dilute caustic alkali it imparts 



a yellow colour, but a small portion only is 



dissolved ; and as nothing is thrown down by 



supersaturation with acetic acid and ferrocy- 



anate of potash, it is not albumen that is taken 



up : the acid solution, however, is copiously 



precipitated by infusion of galls, so that it 



contains some peculiar principle. The residue 



which resists the action of dilute alcali, when 



boiled in concentrated solution of caustic pot- 



ash, becomes brown, and smells like horns imi- 



larly treated; a part of it seems to form a 



compound with the alkali insoluble in the ley, 



but soluble in water, in which respect it re- 



sembles horn, but it differs from it in not 



being precipitated from its solution by muriatic 



acid, nor ferrocyanate of potash, and scarcely 



by infusion of galls. It appears, therefore, 



that cerumen is an emulsive combination of a 



soft fat and albumen, together with a peculiar 



substance, a yellow and very bitter matter 



soluble in alcohol, and an extractive substance 



soluble in water: its saline contents appear to 



be lactate of lime and alkali, but it contains 



no chlorides and no soluble phosphates. When 



cerumen accumulates and hardens in the ear so 



as to occasion deafness, it is easily softened by 



filling the meatus with a mixture of olive oil 



and oil of turpentine, by which its fatty matter 



is dissolved. 



( W. T. Brande.) 



CERVICAL NERVES. 



NERVES. 



See SPINAL 



CETACEA; Gr. KJJTJJ, sA<pK>, Aristotle; 

 Eng. Whale tribe, Cetaceans ; Fr. Cetaces ; 

 Germ. Wall-fische. 



[An order of mammiferous animals, distin- 

 guished, as regards outward characters, by the 

 absence of hinder extremities, neck, hair, and 

 external ears; and by the presence of a large 

 horizontal caudal fin, and the fin-like form of 

 the anterior extremities, the bones of which are 

 shortened, flattened, and enveloped in a thick 

 unyielding smooth integument. With this con- 

 figuration the Cetaceans are fitted only for 

 aquatic life, and reside habitually in the waters 

 of the sea or of large rivers : their resemblance 

 to the true Fishes is so close that many natu- 

 ralists, since the revival of literature, and the 

 vulgar in all ages, have regarded them as mem- 

 bers of the same class. Aristotle, from his 

 anatomical knowledge, was aware of the essen- 

 tial differences between the Whales and Fishes, 

 but it is not absolutely necessary to seek for 

 internal characters to establish the real distinc- 

 tion which subsists between these different de- 

 nizens of the deep ; the horizontal position of 

 the tail-fin at once distinguishes the cetacean 

 from the fish, in which that fin is vertical. This 

 difference relates to the different nature of 

 the respiration of the Whale, which is by 

 lungs, and consequently necessitates a frequent 

 rising to the surface of the water to breathe the 



