638 ME. J. E DUEBDEK ON THE RELATIOKS OF 



the Caribbean Sea ; and C. australis, Hadd. & Duerd., and 

 C hoplites, Hadd, & ShacH., in Australian waters. 



Kwietniewski (1896, p. 597) has recently described the anatomy 

 of (7. carnea. Stud., and that of most of the other species is now 

 known. The genus is distinguished externally by the tentacles 

 being distinctly knobbed, the outer larger than the inner, and 

 arranged in radial rows in different series, more than one tentacle 

 communicating with an endocoelic chamber. 



In the following characters the three Actiuiarian genera 

 mentioned admit of a comparison with the Madreporaria. In 

 many respects the deep-sea genus CorallimorpJius^ described by 

 Moseley and by E. Hertwig (1882, p. 21), also presents suggestive 

 features. 



Disc and Ccenosaec. 



In by far the majority of Actiniaria the disc is approximately 

 circular, and one series of tentacles surrounds only one mouth. 

 On the other hand, many coral genera, such as Mceandrina, 

 Manicina, and Mycedium, produce a permanent mseandriform 

 disc, on which are numerous oral apertures surrounded by but 

 one system of tentacles, the whole being the result of intra- 

 calycinal fission. Compound examples of the anemones Ricordea 

 and JRhodactis are often met with, their outline exactly recalling 

 that of such a familiar "West-Indian coral as Manicina areolata. 

 The multioral disc, instead of being circular, presents the begin- 

 ings of a mseandriform condition. Where the polyps possess 

 only one mouth they are circular in outline and small, apparently 

 just separated by division from some compound larger example. 

 The multioral state is more usual in Ricordea than in RJiodactis, 

 Duchassaing and Michelotti (1860, p. 41) first recorded it for 

 Ricordea florida, and regarded the occurrence of five mouths a& 

 normal in the adult. McMurrich found the peculiarity less 

 developed in Bahaman representatives, while in my experience 

 it is very general in the abundant Jamaican specimens. One 

 example presented as many as seven distinct mouths on an 

 irregularly-shaped disc, and there is probably no definite limit tO' 

 their number. 



Though not so common in Rhodactis Sancti-Thomoe, polyps 

 with two or three mouths on one disc, and not displaying any 

 evidence of further division, are often collected. In both species- 

 nearly all sizes of polyps are closely associated in the large areas 



