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the palate, with a bare interval along the middle line. These plates 

 are placed transversely to the long axis of the palate, with very short 

 i nt rivals between them. Each plate or blade is somewhat triangular 

 in form, with the base attached to the palate and the apex hanging 

 down wauls. The outer edge of the blade is hard and smooth ; but 

 the inner edge and apex fray out into long bristly fibres, so that the 

 roof of the Whale's mouth looks as if covered with hair, as described 

 by Aristotle. At the inner edge of each principal blade are two 

 or three much smaller or subsidiary blades. The principal blades 

 are longest near the middle of the series, and gradually diminish 

 towards the front and back of the mouth. The horny plates grow 

 from a dense fibrous and highly vascular matrix, covering the 

 palatal surface of the maxilla?, and sending out lamellar processes, 

 one of which penetrates the base of each blade. Moreover, the 

 free edge of these processes is covered with very long vascular 

 thread-like papilla?, one of which forms the central axis of each of 

 the hair-like epidermic fibres of which the blade is mainly composed. 

 A transverse section of fresh whalebone shows that it is made up of 

 numbers of these soft vascular papilla?, circular in outline, each 

 surrounded by concentrically arranged epidermic cells, and the 

 whole bound together by other epidermic cells, that constitute the 

 smooth cortical (so-called " enamel ") surface of the blade, which, 

 disintegrating at the free edge, allows the individual fibres to 

 become loose and assume the hairdike appearance before spoken of. 

 These fibres differ from hairs in not being formed in depressed 

 follicles in the enderon, but rather resemble the fibres composing the 

 horn of the Rhinoceros. The whalebone in fact consists of nothing- 

 more than modified papilla? of the buccal mucous membrane, with 

 an excessive and cornified epithelial development. The blades are 

 supported and bound together for a certain distance from their 

 base by a mass of less hardened epithelium, secreted by the surface 

 of the palatal membrane or matrix of the whalebone in the intervals 

 of the lamellar processes. This is the " intermediate substance " of 

 Hunter, the " gum " of the whalers. Baleen varies much in colour 

 in different species. In some it is almost jet black, in others slate- 

 colour, horn -colour, yellow, or even creamy- white. In some the 

 blades are variegated with longitudinal strips of different hues. 

 Baleen differs also greatly in other respects, being short, thick, 

 coarse, and stiff in some, and greatly elongated and highly elastic 

 in those species in which it has attained its fullest development. 

 Its function is to strain the water from the small marine molluscs, 

 crustaceans, or fish upon which the Whales subsist. In feeding the 

 immense mouth is filled with water containing shoals of these small 

 creatures, and then, on the Whale closing the jaws and raising the 

 tongue, so as to diminish the cavity of the mouth, the water streams 

 out through the narrow intervals between the hairy fringe of the 



