56 ACALKPII.F. 



The larger Actinia, milk-white, with orange disc and tentacle-, is 

 found sparingly between 120 and 195 fathoms. The smaller appears 

 to live unattached in sand, in about 90 fathoms: it is of brownish color, 

 and disk-shaped when contracted. 



A Palythoa not very different from /'. ocettata Lamx. from the Florida 

 coast is quite common, ranging from 35 to 287 fathoms, attached in 

 considerable numbers to foreign bodies. 



A large black Palythoa appears to live solitary in 42 fathoms. 



One specimen of an Ilyanthus was found in 124 fathoms, off Tor- 

 tugas. 



A disk-shaped Actinian covered with sand was obtained in 85 fathoms 

 off Tennessee Eeef, and in 91 and 93 fathoms oft" Bahia Honda and off 

 the Samboes. It probably belongs to the new genus Ammodiscus 

 Carpenter, dredged off the coast of Portugal. It is not destitute of ten- 

 tacles in my specimens. 



Ordeb AC ALE PIKE. 

 Suborder HYDROIDE.E Johnston. 



MILLEPOPJD.E Agass. 



Milleporida M-Enw. & H. 



Since Professor Agassiz's first announcement of the affinities of the 

 Millepores with the hydroid polyps, it does not appear that new obser- 

 vations have been made on the subject, although twenty years have 

 elapsed since. The polyps of Millepora are very difficult to observe, 

 not only on account of their very small size, but also because they re- 

 quire peculiar care in collecting, being killed by the shortest contact 

 with air. If they have finally expanded, after much patient waiting on 

 the part of the observer, the least shock to the vessel, or attempt to 

 bring the specimen in a convenient position, is sufficient to make the 

 polyps contract instantaneously and often finally. I have succeeded 

 but once in having a good view of one of the larger polyps of Mille- 

 pora ahicomis, in company with Professor Agassiz. It differed from the 

 figure in the " Contributions to the Natural History of the United 

 States," Vol. III., Plate XV.. fig. 0. in being comparatively shorter, and 

 having larger tentacles or rather tentacular masses studded with lasso 

 cells, five in number instead of four. The mouth was not seen very 



