ST. VINCENT, CAPE VERDE ISLANDS. 



49 



down towards the surf as the only escape, and as it saw a wave 

 rushing up the shelving shore dug itself tight into the sand and 



OCYPODA IPPEUS. 



(About half natural size.) 



held on to prevent the undertow from carrying it down into the 

 sea. As soon as the wave had retreated, it made off full speed 

 along the shore. I gave chase, and whenever a wave approached, 

 the crab repeated the manoeuvre. I once touched it with my 

 hand whilst it was buried and blinded by the sandy water, but 

 the surf compelled me to retreat, and I could not snatch hold of 

 it for fear of its powerful claws. At last I chased it, hard 

 pressed, into the surf in a hurry, and being unable to get proper 

 hold in time it was washed down into the sea. 



The crab evidently dreaded going into the sea. These sand- 

 crabs breathe air through an aperture placed between the bases 

 of the third and fourth pairs of walking legs, and leading to the 

 gill chamber. They soon die wdien kept for a short time 

 beneath the water, as shown by Fritz Muller's experiments* 



A lizard or gecko is very common both at St. Vincent and 

 San Jago. It appears to be the Tarentola Delalandii of Madeira, 

 or closely allied to this. 



* " Facts and Arguments for Darwin," p. 33. London, John Murray, 

 1869. 



E 



