CEPHALOPODA. 



49 



The shells of Spirilla (Fig. 44) have been long known, and are 

 scattered in thousands on the shores of New Zealand and other 

 islands in the Pacific Ocean, and they are also found in the Indian 

 and Atlantic Oceans, occasionally drifting on the coast of Devon and 

 Cornwall. Notwithstanding the abundance of the shells, very few 

 specimens of the perfect animal have been captured. The loosely- 

 coiled shell resembles a ram's horn, and is divided into a number of 



Fi?. 44. 



The Spii'ula (Spirula peronii). (From the Indian and Pacific Oceans.) 



1. Animal : a, portions of the shell exposed in front and behind; h, the funnel 

 or siphuncle. 2. Side view of shell. 3. Shell in section, to show partitions 

 or septa. [Wall-case on east side of gallery.] 



segments by fine concave partitions, like the shell of Nautilus, each 

 one pierced by a slender tube or siphon. It is almost entirely 

 enclosed within the hinder end of the body, only a small portion 

 of it being exposed in front and behind. Absolutely nothing is 

 known of the habits of this very interesting creature, although 

 probably they are somewhat similar to those of other Cephalopods. 

 It is possible that it may live at a considerable depth. 



The Nautilus (Fig. 45), of which several shells (Case 208) and a 

 perfect animal in spirit (black upright case A) are exhibited, is an 

 inhabitant of the Indo-Pacific Ocean, and differs from all other 

 living Cephalopods in being provided with four instead of two gills, 

 and, instead of eight or ten arms with suckers and hooks, has a 



E 



