105 



is sufficiently deepened, the eyes are again brought forward, the 

 antenose are thrown back in a line with the body, and the animal 

 fsrces its head in the hole it has made ; this is facilitated by the 

 body being gradually raised by means of the fifth pair of legs ; the 

 head being inserted, the burrowing continues with inereased energy, 

 and the animal assumes the position as in photograph No. 2 ; thi3 

 view shovTs the sand which has been thrown up accumulated in a 

 heap under the body. 



I have occasionally found it continue in this position, but gene- 

 rally it burrows perpendicularly, until only the tips of the antennse 

 are visible. 



I placed my captive in a glass vase, and he having selected the side 

 of the glass for burrowing (probably from the glass forming one firm 

 side to the work), enabled me to watch every moveraent ; the sand 

 appeared to be passed to the mouth of the hole by the legs and falše 

 legs, when it fiUed round the body and filled in as the animal passed 

 downwards. The antennse are delicately sensitive. I believe this 

 sensitiveness depends on the seuse of touch : the slightest contaet 

 •with them sets the animal in motion (and this when it is buried 

 Bome depth), using every exertion to burrow deeper. It is evidently " 

 a night-feeding genus, as it remained buried and inactive during the 

 day, but the statė of the sand in the tank in the moming proved 

 that it had not been idle during the night. 



From these facts I am justified in stating that NiJca edulis is a 

 burrowing species (if not of a burrovving genus), and that its bur- 

 rowing is only by day to hide itself from its enemies, and not to 

 procure food. 



The description I have given of the colouring of this species will 

 be found to be different from that given by Risso, as stated by Mr. 

 Milne-Edwards. I should have great diffidence in differing from 

 these eminent naturalists had I not imagined that their descriptions 

 might have been taken from cabinet specimens. Had I waited to 

 describe my specimen until after its death, I mušt have described it 

 as it now is, namely, Jlesh-red ; I find all the thinner-shelled Crus- 

 tacea change more or less of a flesh-red, with the exception of the 

 Crangonidce. 



The different plaus of burrowing in the different genera are very 

 interesting, and may probably be given in another paper. 



The photographs to illustrate these notes represent 



No. 1 and No. la. — Niką edulis (natūrai size) taken from a 

 living specimen (on a collodion plate) in two different positions. 



No. 2. — The šame (natūrai size) when partially buried. This 

 view shows the sand accumulated under the body of the animal. 



No. 3. — A view of a portion of Weymouth Bay, taken by a col- 

 lodion negative. The camera being sunk in tvvo fathoms of water, 

 the line of demarcation between the water and air is here plainly 

 visible. 



No. 4. — A photograph of Aphrodita aculeata taken (in two dif- 

 ferent positions) from a living specimen two-thirds of its natūrai 

 size. 



