11G BULLETIN OF THE 



genus Errina as defined bolow. It is here retained among the Stylastcrs 

 on account of its distinct septa and the absence of tubular pores having a 

 longitudinal fissure below. On the other hand the passage through St. 

 flaheliiformis to the Stylasters with round scattered calicles appears natural. 

 When I have had more opportunity of examining the allied forms, it may 

 be necessary to separate S. complanatus generically from the true Stylasters. 

 The whole group of corals comprising the genera Stylaster, Errina, Allo- 

 pora, and Distichopora, all closely allied, requires careful revision. 



Genus Errina. 



A comparison of specimens of Errata aspera Gray, in the Museum of Com- 

 parative Zoology in Cambridge, with the two species described below, 

 showed very plainly that Gray has overlooked the true calicles and mis- 

 taken for them the tubular pores scattered over the younger branches. 

 In his species these pores are very large and numerous, and the calicles 

 small and concealed ; in the new species, here described under the name 

 of St. cocJdeatus, the reverse is the case. The structure of the latter spe- 

 cies being once well understood, it is very easy to recognize the same parts 

 in the other ; of both 1 have furthermore made careful sections for the 

 microscope. Whilst retaining the name adopted by Gray, I propose the 

 following generical definition. 



Corallum branching, subfiabellate, finely granulated or obscurely stri- 

 ated, the younger branchlets more or less studded with tubular pores, split 

 downwards >'nto a furrow. Calicles at first terminal, in shape of a trans- 

 verse slit, of which one lip continues to grow in a conical shape to repeat 

 the process, whilst the other expands in the shape of a bract or spoon, hid- 

 ing the calicle alter it has become lateral. Fossa circular and very deep; 

 septa obscure or none; pali rudimentary in the shape of sin ill beads; colu- 

 mella pistilliform. Ampulla? as in Stylaster. 



Errina cocnlcata Potjrt. 



Corallum branching, very slender, subfiabellate, finely granulated and 

 striated, studded with echinulated ampullar. Branchlets almost filiform; 

 the pores on them are sometimes tubular with a longitudinal fissure below. 

 Fossa round and deep, the spoon-shaped lip hiding it entirely. Columella 

 pistilliform and somewhat hirsute, very deep seated. Septa few and indis- 

 tinct, formed by folds of the wall. 



Compared with T£mna aspcra from Fayal, it is found to differ from it in 

 having slenderer branches, with fewer and smaller furrowed tubercles and 

 fewer echinulated ampullffl, whilst the calicles are larger and more con- 

 spicuous. The whole corallum is about one inch high. Found in "270 

 fathoms oil' Havana. 



