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Show 498 PROF. J. E. DUERDEN OX CRABS [Dec. 12, found them on the under surface of blocks of coral. When kept in the laboratory they would sometimes come from under the corals and wander over the living polyps. The following observations were made upon the two specimens of Melia, and a few notes are added upon an example of Poly-dectus- another crab obtained which likewise bears actinians in its claws. The first Melia collected carried a Bunodeopsis in each claw. One of the actinians was fully grown, while the other was a mere fragment having two or three large tentacles and several imperfect members. The polyps were held across the column, the tentacular disc directed upwards and the aboral disc downwards ; so that when at rest the crab presented the appearance depicted in fig. 74, where, however, the tentacles have been increased to their usual number. Usually the crab travelled with its claws extended a little forwards, sometimes waving them and the actinians from side to side. Text-fig. 74. Lelia tessellata from the Hawaiian Islands, bearing' an expanded actinian in each claw. When food is placed on the disc ot the actinians, the first ambulatory limbs of the crab reach over and abstract it and pass it to the crab's mouth. The actinians were grasped rather loosely, the claws of the crab being about halfway open, and with a little care it was possible to free them, though sometimes the minute spines on the inner side of the claws (text-fig. 75, p. 500) wrould penetrate and tear the polypal wall as described by Mobius. The claws seemed very feeble and during the operation remained open, making none of the attempts to close and grasp objects, such as one usually experiences when experimenting with crabs. The imperfect polyp wras torn during its removal, a minute fragment being left on the chela; but the laigei piece quickly recovered from its injuries and expanded its tentacles to their full degree. The second Melia held two small sagartiids, these actinians being of an altogether different type from the Bunodeopsis. oth polyps were of about the same size, and were likewise held across the middle of the column in a partly expanded condition, he tact that the two specimens of Melia held different forms of |
