14 ST. THOMAS. 



was formerly used for holding sand to sift over writing instead 

 of blotting-paper. It was boiled in oil when gathered, and this 

 prevented its flying asunder. The fruit I gathered went off 

 with considerable violence when I touched it one day on 

 board ship after it was dry, but it did not make much noise. 



Another Euphorbiaceous tree, the Manchineel, grows in St. 

 Thomas, and its juice is almost as poisonous as that of the 

 " Sand-box " tree. The fable ran that if a man allowed rain 

 to drop off its leaves on to his skin, his skin would be burned 

 and inflamed by it. 



I landed one day on one of the small outliers of St. Thomas, 

 Little Saba Island, about a mile and a half distant from the 

 main island. A puffin {Fuffimis sp.) was nesting in holes 

 amongst the grass, laying a single large white egg. The birds 

 allowed themselves to be caught in the nest with the hand. 

 Our spaniels kept bringing them to us, retrieving them with 

 great delight. The island was covered with thorny cactuses. 

 It was impossible to avoid their prickles, and I got covered 

 with them when in pursuit of wild goats and pigeons. There 

 were four kinds of cactuses, a prickly-pear {Opuntia) with 

 spines three-quarters of an inch long ; a quadrangular stemmed 

 cactus, like the most familiar one in green-houses ; a cactus 

 with rounded ribbed stem, growing in candelabra-like form 

 {Cereus), and a large dome-shaped cactus, a foot and a half 

 high and bearing a crown of small red flowers {Melocactus). 



The spines must be a most efficient protection to the cactus 

 from being devoured by large animals. I have often noticed 

 that if one approaches one's hand slowly towards some of the 

 forms with closely-set long spines, doing it with especial care 

 to try and touch the end of one of the spines lightly without 

 getting pricked, one's hand always does receive a sharp prick 

 before such is expected, the distance having been miscalculated. 

 There seems to be a special arrangement in the colour of the 

 spines in some cases, possibly intended directly to bring about 

 an illusion, and cause animals likely to injure the plant to get 

 pricked severely before they expect it, and thus to learn to 

 shun the plant. Whilst the greater length of the spines next 

 the surface of the plant is white, the tips are dark-coloured or 

 black. The black tips are almost invisible as viewed at a good 

 many angles against the general mass as a background. The 

 spines look as if they ended where the white colouring ends, 

 and the hand is advanced as if the prickles began there, and 

 is pricked suddenly by some unseen black tip. The experi- 

 ment is easily tried in any cactus house at home. 



In the beach of Litde Saba Island there was being formed a 

 reddish sandstone conglomerate rock composed of the debris 



