VOL. XVI 



is'j;!. 



] PROCEEDINGS OF THE NATIONAL MUSEUM. 201 



Tlie mouth is very prominent, and sliows indistinct traces of a dark, 

 slate-gray pigment. Tlie mesogkea of its lips is thickened, the thick- 

 ening gradually thinning out, both towards the disc and towards the 

 stomatodanim. This is marked with longitudinal ridges, supported 

 by mesogloial elevations, and possesses deep siphonoglyphcs. 



There are ninety-six pairs of mesenteries. Twelve of them, repre- 

 senting the first two cycles, are perfect, the rest imperfect, the fifth 

 cycle of forty-eight pairs being very small, hardly projecting above the 

 endoderm. lleproductive organs are borne upon the forty-eight mes- 

 enteries composing the third and fourth cycles. • No acontia are pres- 

 ent. The longitudinal nuiscles of the mesenteries (PI. xxxiv. Fig. 114) 

 have a moderate degree of development, forming a rather dittiise pen 

 non. The parieto-basilar is, however, strong, forming a welhmarked 

 pouch upon the surface of Ihe more developed mesenteries. 



Very decided differences exist between this form and 7>. anemone 

 previously stmlied by me ('89), but nevertheless a general similarity is 

 well marked, showing itself in the shape and structure of the tenta- 

 cles, the character of the sphincter muscle, and the deep siphonoglyphe. 

 The musculature of the mesenteries has, however, a very different 

 ariangement, and the relationship of the perfect and imperfect mesen- 

 teries is quite different. These points, however nuiy be justly regarded 

 as specific. 



Tribe CERIANTHE^E. Ilert. 



Anthozoa, with a large number of unpaired mesenteries, and with a 

 single siphonoglyphe; the eight Edwardsiau mesenteries are situated, 

 four on each side, at the sulcar surlace, and new mesenteries are added at 

 the sulcular surface, being interposed, one on each side of the sagittal 

 plane, between those immediately preceding them in time of formation. 

 The base is not adherent and is usually provided with a poie ojiening 

 into the body-cavity. Column Avails, with strong ectodermal mus- 

 culature. 



Family CEllIANTHID^. 

 With the characters of the tribe. 



Genus CERIANTHUS, Delia Cliiaje. 



Whether the form described below be correctly referable to the genus 

 Cerianthus is questionable, inasmuch as it seems to differ in several 

 particulars from any of the forms hitherto referred to the genus. An- 

 dres ('83) divided the forms assignable to the family (Jerianthidie into 

 three genera (not including Arachnactis), but the characters upon Avhich 

 these genera were based hardly seem at present of sufficient importance 

 to be cousidered generic. It seems to me preferable, at present, to 

 assign the specimen described below to Delia Ohiaje's genera rather 

 than to establish a new genus on insulficiently understood characters. 



