118 



The columella, though deep-seated, is large and prominent : it 

 is nearly circular and consists of a loose spongy reticulum. 



An average, nearly fullgrown, corallum, with 36 septa, is 12 

 millim. long, the diameter of its mouth inside the prominent 

 epithecal lip being 7 millim. 



Citliarocyatlms , n. gen. 



Corallum simple, cylindro-conical, free without any tracé of 

 early adhesion, naked. Costa? denticulate. Columella fasciculate, 

 well developed, 



There is a single crown of pali standing in front of the septa 

 of the second cycle, each palus being formed by the V~ Süa P e d 

 union of processes from the septa of the third cycle. 



This genus is closely allied to Deltocyathus: it also seems to be 

 nearly related to Nototrochus Duncan (= Notocyathus Tenison 

 Woods). From Conocyathus d'Orb., which it also strongly resem- 

 bles, it differs in possessing a columella. In mere external ap- 

 pearance it looks like Turbinolia. 



3. Citliarocyatlms conicus, n. sp. 



Corallum free, straight, moderately elongate, acutely and very 

 elegantly conico-cylindrical. 



Costae continuous from the pointed base to the calicular mouth, 

 broad and close-set but very deep-cut, crisply granular and echi- 

 nulate, all of one size. Those of the first cycle are independent 

 throughout their course, but those of lower orders are united by 

 successive bifurcations to form series of figures like the Greek 

 letter psi. 



Mouth of calicle nearly circular. The calicle, though deep, is 

 much filled up by the septa etc. 



Septa elegantly and copiously denticulate, arranged very regu- 

 larly in six systems and four cycles, only slightly exsert. Those 

 of the first cycle, which are the largest, are independent and 

 may unite with the columella. Those of the third cycle, though 



