34 MR. A. W. WATERS ON THE MARINE 



somewhat larger than those of the uniserial forms (figs. 2, 8), and this 

 bi-multiserial form is provisionally called var. composita. 



Returning to the uniserial forms it is in these that the ovicells have been 

 found, and the zoarial growth is similar to that of Radiopora Francquana, 

 d'Orb* 



The central depressed region of each subcolony has large pores (about 

 - 07 mm.) about the size of those of tbe zooecia, whereas the pores between 

 the rays are usually smaller. The inner zooecia of a ray are the most raised, 

 whereas in var. composita there is very little difference — in fact, most seem cut 

 off nearly straight, without being apparently worn ; in this uniserial form 

 the zooecia are well raised, and especially near the edge of the colony the 

 spinous processes are more pronounced than in the variety. In the British 

 Museum specimen from Madeira t, in the Norman collection, most of the 

 zooecia show a blunt spinous process at the outer border and occasionally on 

 both the inner and outer, also the internal pin-head spines in the cancelli are 

 very small and rather rare. In one colony, from Cape Verde Islands, there are 

 two ovicells, which are very narrow and interdigitate in narrow bands 

 between the rays (figs. 2, 6). The surface of the ovicell has numerous fine 

 perforations. Another colony has a very deep pit in the centre of several of 

 the subcolonies (fig. 5), but, on carefully focussing to the base of one pit, the 

 narrow bands of a similar ovicell are seen, so that we are looking upon the 

 upper part of an ovicell now at the bottom of tbis pit, and a zoarial growth 

 must have taken place subsequent to the formation of the ovicell, but whether 

 it indicates a regular second layer it is impossible to say. In one zoarium, 

 in the centre of a subcolony, the base is found of an ovicell in formation, 

 which is smooth and imperforate, proving that in the case previously 

 mentioned we were not looking on the base of an ovicell at the bottom of the 

 pit. In the section of another Lichenopora I have seen an ovicell in two 

 stories — that is, one ovicell above another. 



Harmer J describes and figures a similar ovicell in what he calls 

 Lichenopora novce-zelandice, Busk, but it is unfortunate that he should have 

 taken the name novce-zelandice apparently because it was published a page 

 sooner than L. Holdsworthii, Busk, for this latter is well described from 

 characteristic specimens found in Ceylon. On the other hand, the description 

 and figure of novce-zelandice were not very satisfactory, and among the 

 specimens which Busk so named in his collection there seem to be more than 

 one species. I have some specimens which have always seemed to me to be 

 this species, and one from New Zealand was sent to me so determined, also 

 the British Museum specimens have been looked through more than once, 



* Pal. Fran?, pi. 782. figs. 3-8. 



+ In one case the ovicell only throws out arms on one side of the subcolony. There are 

 some deep pits as described in the Cape Verde Islands specimens. 



\ Polyzoa of the 'Siboga' Expedition, pt. i. p. 155, pi. 12. fig. 11 (1915). 



