46 OK THE BONNET OF THE SOUTHERN BIGHT WHALE. [Feb. 5, 



also l^athusius, Arch, f . Anat. u. Phys., Leipzig, 1869, pp. 76-80), 

 and in baleen or "whalebone," in which a strongly marked, 

 superficial, stratified layer is present in addition, especially m the 

 basal parts (fig. 6 : see also Milne-Edwards, Lecons sur la Physiol, 

 vi., Paris, 1860, p. 120). The stiff" hairs on the tail of the Elephant 

 are described by Naunyn * as intermediate in character between 

 simple hairs and Ehinoceros horn. Even the horns of Oxen and 

 Goats show, in their deeper, most recently formed layers, a closely 

 analogous structure. This becomes lost in the outer layers in 

 consequence of the compression which the fibres undergo— they 

 first become elliptical or crescentic in section, and finally so flattened 

 that the outer layers exhibit a marked stratification. 



The skin of Whales is peculiar in structure'. Not only is it 

 practically hairless in the adult condition, but it is devoid of 

 glands, and cutaneous nerves are scarce. The stratum corneum is 

 very thin, but the rete inalpigJiii is strongly developed, and is 

 traversed by numerous very long, vascular papillae. The corium, as 

 a layer, is in most cases almost completely wanting. 



Elongated, fingei--like papillae of this kind are, be it observed, 

 not confined to Whales. They occur in most cases where the 

 skin attains an unusual thickness, and they serve the purpose, as 

 Leydig^ pointed out, of supplying nourishment to a thickened 

 epidermis, since the epidermis, being but slightly pervious, cannot 

 absorb the nourishing plasma through more than a limited thickness 

 of its substance. Long papillae were remarked by Steller in the 

 skin of Eliytina ; they occur in the skin of the Hippopotamus, 

 particularly in the region of the upper lip *, in the hairless skin on 

 the muzzle of the Ox% in the snout of the Pig, and on the point of 

 the proboscis of the Elephant ^ 



I have not had an opportunity of examining sections of the skin 

 of the Whale, but the published descriptions go to show that the 

 structure of the " bonnet " under consideration does not differ in 

 essential features from that of the stratum corneum of the normal 

 skin ; for this exhibits just the same disposition of the cornified 

 cells. Heusinger, for instance, in describing the skin of Balcena 

 mysticetus, writes : — " Die Lederhaut ist ausserst diinn oder fehlt 

 ganz ; dagegen findet sich eine mehr als zoUdicke Schicht, die aus 

 paraUelen, dicht mit einander verklebten und verwachsenen Easern 

 besteht : zu unterst, wo sie auf dem Fette standen, sind diese 

 Easern am dicksten, nach obeu werden sie diinn und sind schwer 



1 Arch f. Anat. u. Phys. 1861, p. 670. 



^ Leydig, F., "Ueber die ausseren Bedeckungen der Saugethiere," Arch, f 

 Anat. u. Phys. 1859. 



Kiikenthal, W., " Die Haut der Cetaceen," Denkschr. d. med.-nat. GesplI 

 iii., Jena, 1889. 



^ L. c. p. 701. 



* Leydig, I. c. ; and Weber, M., ' Studien liber Saugethiere,' Jena, 1886. 



^ Nathusius, W., "Ueber die Marksubstanz verschiedener Horngebilde," Arch, 

 f. Anat. u. Phys., Leipzig, 1869, pi. iii. fig. 11. 



^ Smith, F., "Histology of the Skin of the Elephant," Journ. Anat. & Phys. 

 xxiv. 1890. 



