ON THE SOLITARY CORALS, COLLECTED BY DR A. WILLEY. 179 



Fig. 17. An aberrantly shaped free anthocyathus with six cycles of septa. 



(a) Oral view. 



(b) Aboral view showing the scar still very distinct. The whole surface has been 

 much overgrown and killed except near the edges by incrusting organisms. Some of the 

 costae, however, can be directly traced into the septa of the scar. 



Fig. 18. Oral view of the young free anthocyathus, the scar of which is represented 

 in Fig. 14. Five cycles of septa are complete. 



Fig. 19. Aboral view of the smallest free anthocyathus. The corallum is nearly closed 

 in below, but the edges of the septa in the scar are still very ragged and distinct. 



Fig. 20. A large irregular, attached anthocyathus. 



Oral view, .Six cycles of septa are complete and on the broad side the seventh 

 cycle also. 



(6) Aboral view. In the centre is the stem, to which the anthocyathus is attached. 

 It is an anthocaulus, from which one anthocyathus has already separated, the ring left by 

 which can be seen in places. 



Fig. 21. An anthocyathus almost ready apparently to detach itself from its stalk. 



(a) Oral view showing six complete cycles of septa. 



(b) Aboral view. In the centre is the stalk, round which immediately under the 

 horizontal outgrowth can be seen a distinct pitted ring, where the anthocyathus will 

 subsequently be detached. 



Fig. 22. Profile view of a young anthocyathus, attached to an anthocaulus, which is 

 itself fixed on a dead free anthocyathus, from which it was probably in the first place 

 budded. There is one ring of detachment of a former anthocyathus. 



Fig. 23. Profile view of a still younger anthocyathus on an anthocaulus with three 

 rings. Even at this size a trace of the pitted ring, where the anthocyathus will subsequently 

 be detached, is visible. The anthocaulus is attached to a fragment of a dead free antho- 

 cyathus, to the under surface of which the three youngest trophozooids, two of which are 

 represented in Figs. 10 and 11, are attached. 



Fig. 2-1. A young anthoblast (trophozooid ?) with four cycles of septa complete, 

 (a) Profile view (xl). 

 (6) Oral view (x 2]). 



Fig. 25. Deltocyathus ornatus, n. sp. 



(a) Aboral view (x 2J). The costae commence as rows of low granules, gradually 

 passing from a slight prominence in the centre into broad rounded ridges towards the 

 exterior. The primary, secondary and quaternary septa are equally exsert, while the 

 tertiaries — twelve — project considerably further. 



(6) Oral view (x 2\). The primary and secondary septa closely resemble one 

 another, but can be seen in most of the systems to run much deeper into the corallum 

 and to have less elongated paUform lobes than the tertiary septa, which are much more 

 exsert. In places the quaternary septa can be seen bending in towards the tertiaries with 



