Ch. XIII.] NEW SPECIES OP PHYLLIDIA. 219 



coral ; but, if caught, shutting themselves up as if in a box, 

 from the curious compact manner in which their legs all 

 fitted under the vault of their carapace. Large rough-rayed 

 starfishes (Ophiocomas) also lurked in holes ; and I re- 

 marked as a fact worth noticing that, fragile as they are, I 

 could, by tuggiag at one arm or ray, puU one of these brittle- 

 stars by maia force out from a hole scarcely large enough to 

 admit the passage of its body, and yet without breaking it ; 

 whereas, two minutes after, holding it suspended by one 

 arm, it broke short off, evidently amputated by the will of 

 the animal. And, lastly, I found myself the possessor of 

 two new and very beautiful species of PhyUidia, animals 

 closely allied to the Doris, but having the giUs arranged in 

 a lamellar form along the sides of the body, instead of on the 

 back, as in the Nudibranchs. One of the^se was richly 

 •tuberculated with shades of green upon a jet-black ground ; 

 in the other, the tubercles were of a more simple character — 

 rose-pink in some examples, in others (evidently, however, 

 the same species) of a pale emerald green. 



