498 PROF. J. E. DUERDEN ON CRABS [DeC. 12, 



found them on the under surface of blocks of coral. When 

 kept in the laboratory they would sometimes come from under 

 tlie 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 Bunodeojisis in each claw. 

 One of the actinians was fully grown, while the other was a mere 

 fi'agment having two or three large tentacles and several im- 

 perfect 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. Usvially the crab travelled with its claM'S 

 extended a little forwards, sometimes waving them and the 

 actinians from side to side. 



Text-fio-. 74. 



Jlelia tesseUata from the Hawaiian Islands, bearing an expanded actinian in each 

 claw. When food is placed on the disc of 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 

 1)eing 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) would penetrate and tear the polypal 

 Avail as described by Mobius. The claws seemed very feeble and 

 <luring the operation remained open, making none of the attempts 

 to close and grasp objects, such as one usually experiences when 

 experimenting with ciubs. The imperfect polyp was torn during 

 its removal, a minute fragment being left on the chela; but the 

 larger piece quickly recovei-ed fi'om its injui'ies 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. 

 Both polyps wei'e of about the same size, and were likewise held 

 across the middle of the column in a partly expanded condition. 

 The fact that the two specimens of Melia held different forms of 



