738 



EXTERNAL FORM AND PIGMENTATION. 



at the time of its capture. Professor Owen, we are told, received the prize and went 

 to Paris to see Cuvier. But Cuvier died shortly afterwards in the same year which 

 witnessed the publication of Owen's memoir, without having had the opportunity of 

 satisfying his instinct of naturalist by the sight of this remarkable creature. 



2. External Form and Pigmentation. 



The external appearance of Nautilus is too familiar to require formal description, 

 especially since an excellent set of drawings representing living specimens in different 

 attitudes has recently been published by Professor Bashford Dean 1 . 



The complete animal consists of the shell and its tenant or, in New Britain 

 parlance, the " pal-a-lialia " and its "wirua," the two being inseparable until parted by 

 death. Although the body is firmly bound to the shell by the tension of the paired 

 columellar muscles, it is not really attached to the shell, the ends of the muscles being 

 covered over with a horny membrane continuous with a horny girdle, so that when 

 the pressure of the muscles is overcome, the entire animal, including the siphuncle, 



Fig. 1. Nautilus pompilius, L., photographed from life in New Britain, 1895. [Reproduced from the Quart. 

 J. Micr. Sc, Vol. xxxix. 1896, p. 179, by permission of the Editor.] About one-half natural size. 



may be removed without lesion, except that the membrane is generally lacerated. The 

 fact that the muscles are not directly attached to the shell was pointed out by Owen 



1 Dean, B., "Notes on Living Nautilus." Amur. Natural., xxxv. pp. 819 — 837, 1901. The material was 

 collected in the strait between the islands of Negros and Cebu in the Philippines. 



