THE EDUCABILITY OF THREE liOCKHNGS. 291 



the forceps were dipped into it, caused the Eoclding to dart 

 excitedly oat of its liole and swim eagerly about the tank. 

 B'rom that day (on whicli it first began to feed from my 

 fingers) the illumination of the tank by any visitor who examined 

 it was sufficient, providing the Eockling was not full fed, to 

 bring the fish from its resting place ; and this might happen 

 several times in the course of an hour. It responded most 

 certainly, however, to the illumination early in the morning, 

 when it was hungry. By the fortieth day a further advance in 

 the education of the Rockling could definitely be noted. It is my 

 custom to introduce the forceps into the aquarium from one par- 

 ticular corner of the tank. It was now observed that when the fish 

 left its hole to look for food it always travelled (round the walls) 

 towards this corner, where it would swim to and fro, and upwards 

 and downwards, in the water. Indeed, it was often the case 

 that when the aquarium was approached with food in the morning, 

 the Eockling was found to be waiting there. On January l8th, for 

 exam]3le, the fish was found at 9.30 a.m. in the corner, moving 

 excitedly to and fro, and it remained there until it was fed at 

 11.15 a.m., after which it retreated to its hiding place. By 

 January 1st (fifty-third day) it could be noted that the Eockling, 

 affected no doubt by the tranquillity of life in an aquarium in 

 which there were no enemies except tiny Swimming-Crabs and 

 small Opelet Sea-Anemones, displayed little or no alarm w'hen it 

 was given a tap with the forceps ; a touch of the forceps during 

 the first fifteen or twenty days of captivity would have caused the 

 fish to dash to its hole ; in January if it retreated at all it did 

 so in a leisurely fashion. On January 18th (seventieth day) two 

 Shore-Crabs were placed in the aquarium, but the presence 

 of these fierce crustaceans did not deter the Eockling from wait- 

 ing for food at the corner of the tank. 



(3) A third Eockling, five inches in length, also from 

 Weymouth, was placed along with the second Eockling on 

 December 8th, 1915. It at once darted to the shelter of the 

 rocks. On the morning of the 9th, when it was partly exposed 

 amongst the rocks, it was offered a piece of mussel in the forceps, 

 but this was refused with signs of fear. It was not until the 

 morning of December 18th (tenth day) that it took pieces of 

 mussel from the forceps, but on this day it also followed the 



