218 PROF. p. MARTIN DUNCAN ON [Feb. 7, 



their sides are oruamented with very decided elevations and depres- 

 sions, forming series of close arches, the convexity being upwards 

 and slightly inwards. The small size of the origin of the septa from 

 the broad costfe is sometimes evident. 



The columella is small and very deeply situate, and is formed by 

 four or five lax trabeculse, which imite with some of the septal ends. 



The costae differ considerably near the base and close to the 

 calice. Near the base they are not numerous ; and in some parts 

 they are slightly developed, subequal or alternately large and small, 

 distinct, and either subcristiform or marked with a row of long, 

 narrow, flat, separate elevations or granules, whilst in others they 

 are alternately large and small, and the intercostal tissue is granu- 

 lar. In the middle of the outside of the coral the costae are larger, 

 subequal, and subcristiform, thin and wavy, and alternately broader, 

 flatter, and granular. Close to the calice they become more nume- 

 rous, cristiform, wavy and oblique, and subequal, the intercostal 

 areas being minutely granular. 



The fractured base shows a thick wall, a columellary tissue, and 

 twelve irregular and short septa. 



The length of the coral is |- inch, and the length of the calice is 

 ^ inch. 



A second and smaller specimen with the same external shape and 

 prevailing decided growth-rings, is younger than that just described. 

 The septa have all the characteristics of those of the first specimen; 

 but the rudimentary ones are absent ; their costae exist however. 



There are not three complete cycles; and the interseptal loculi are 

 very broad. 



The columella is deeply seated, and is formed by tissue, coming 

 irregularly from the ends of some septa. The rough ridges of the 

 sides of the septa are very evident. 



The costae are very distinct, but, as in the other specimen, small ; 

 and their characteristic is their narrow wavy crest near the calice, 

 and their broader and granular nature near the base. 



The fractured base shows nine septa, some primaries and the 

 others secondaries ; but it is not possible to define them. 



Height of the coral | inch, length of the calice rather less than 

 ^ inch. 



The other two specimens are young, and their curved form has 

 only just commenced; they have three perfect cycles of septa, 

 and a small columella deeply seated. The costae of one are broadly 

 granular and subequal near the base ; and near the calice they become 

 shorter, with a tendency to a wavy cristiform shape here and there. 

 In the other the costse are decidedly wavy and crested near the calice 

 and lower down near a growth-ring, and then to the very base. In 

 one instance the base has become incrusted by a Bryozoau. 



Height of coral -^-^ inch. 



As regards the negative characters, it may be said that there are 

 no pali, and that the endotheca is deficient ; moreover the epitheca is 

 only faintly indicated in a young form. The columella is smaller 

 than in the species typical of tlie genus. The positive characters 



