IIOLLUSCA. 275 



the markings of a panther's skin ; and as the little creature 

 moves slightly, either side beneath the fin is seen to glow 

 with metalhc lustre, like that of gold leaf seen through horn. 

 Again, the rings unite and coalesce, and form a beautiful 

 netted pattern of brown, which colour increasing, leaves the 

 interspaces a series of white spots on the rich dark ground/^ 



The Sepiola has a habit of burrowing in the sand. The 

 funnel again comes into play, and by blowing the sand 

 away in puffs, gradually makes a hole large enough to con- 

 tain the animal's body. But if stones, and scraps too large 

 to be blown away, are mixed with the sand, the arms pick 

 them out by means of the sucking discs with which they are 

 furnished. The Cephalo2')oda are supplied with an inky fluid, 

 which they sometimes discharge in a cloud when irritated, 

 for the supposed purpose of hiding from their enemies. 



But MuUusca, as a class, have yet to be studied by 

 means which the Aquarium and the Microscope will place 

 at our disposal. Several varieties of Nudibranchiaie Mol- 

 lusca are figured in Plate XIV. Plate XIII. represents a 

 group of Ascidians, belonging to the Tunicate order, nestled 

 in a bush of Fhi/llophora rubens. 



PhiU'me quad ri partita and its shell are seen at Plate X., 

 in company with Pentactes, 



