8 BRITISH FOSSIL CORALS 



Genus — Trociiosmilia. 



Suh-(jenus — Ccelosmilia. 



L TiiocnosMiLiA (Ccelosmilia) laxa, M. ^- II. PI. Ill, figs. 11—17; PI. IV, figs. 

 9—12. 



In examining good specimens of this species I found the fourth cycle of septa to 

 be present. Its laminae are small, but decidedly visible. Consequently the calice as 

 drawn by MM. Milne-Edwards and Jules Haime (' Monog. Brit. Poss. Corals,' P. I, PI. 

 VIII, fig. 4 c) is incorrect. The following description will apply to three varieties of the 

 species. 



Variety 1. — The corallum is conico-cylindrical and straight. 



The costse are intensely granular inferiorly, and two large costaj are separated by 

 three smaller. Near the calice the larger costse have a wavy cristiform ridge upon them, 

 the intermediate costa? being very granular, with chevron patterns, or they may be moni- 

 liform. At the calicular margin the costse are nearly flat and granular. The fourth cycle 

 of septa is distinct. 



Variety 2. — Inferiorly in structure as variety 1. Superiorly the principal costae are 

 very cristiform, and well marked with a secondary ridge. The chevron markings of the 

 intermediate costse are very distinct. 



Variety 3. — Costse inferiorly wavy and sparely granular. Superiorly the costse are 

 subcristiform and plain, the continuity of the crests being defective. The interme- 

 diate costse are broken and moniliform, and here and there chevroned. 



Localities. — Norwich Chalk ; Wiltshire Chalk. In the British Museum and in the 

 Salisbury Museum. 



2. Trochosmilia (Cielosmilia) cornucopI/E, Duncan. PI. Ill, figs. 6 — 10. 



The corallum is strongly curved in the plane of the smaller axis, and it is compressed 

 superiorly, and is finely pedunculate. The growth rings and swellings are moderately 

 developed. 



The costse are subequal above, and cristate and unequal inferiorly. 



The septa are numerous and very unequal. There are five cycles of septa and six 

 systems. The primary septa are very exsert, and the secondary are less so. The septa 

 of the fifth cycle are very small. 



