44 TIIECOPSAMMIA. 



Thecopsammia socialis Pourt. 



Thcropsammia .soricilis Pourt. Bull. Mus Coiiip. Zoiil., No. 7. 



Plate 11., fig.^. !) and 10. 



Corallum turbinate, rather long conical, with a thick, not much 

 constricted peduncle. Wall and epitheca as in preceding species, 

 but obscure traces of costiv can .sonu'tinies be seen through the 

 epitheca near the iwduncle. Calicle elliptical, moderately deep. 

 St>pta entire, smooth, crowded, not exsert, thick near the wall. Six 

 uner|ual systems and five cycles. The convergence of the septa of 

 the fourth cycle to meet in front of the tertiaries generally plainly 

 visible from outside. The septa of the iifth cycle are developed in old 

 specimens only, and then in i'ew of the systems ; but they soon liecouie 

 very large and encircle the two preceding c3-cles. The tertiaries re- 

 main smallest of all. The columella is papillose and porous, but more 

 compact than in the preceding species, and nearly always forms three 

 distinct masses, of which the middle one is largest. 



This species often forms clusters, several individuals Ijeing united by 

 their bases. 



Height about 2 cm., diameter of cali(de about 13 nun. 



OirComir.s rafcln^s, in lO.-) f;itlioni.>^. 



oil' S(iiiil)HTO Lii,'lithi)iisc, in iC-J CatliDnis. 



This species, according to Dr. Duncsin, has also been found by the 

 "Porcupine" Expedition, in ;]4o and oGo fathoms, in the seas uoith of 

 Scotland. The specimens were more developed than those from 

 Florida, and rather variable, since Dr. Duncan distinguished three 

 varieties. There is a considerable range of variation also in the 

 Florida specimens. I have found in some cases, since the first descrip- 

 tion Avas WTitten, the traces of cost;e which had licen noticed in some 

 of the European specimens. The epitheca is particularly sul)ject to 

 variation, sometimes extending to the edge of the calicle, sometimes 

 confined to the lowest pai'ts of the peduncle. A specimen of the 

 latter category shows distinct granular costie in the bare part of the 

 peduncle. 



