32 THE VOYAGE OF H.M.S. CHALLENGER. 



Porina coronata, Reuss, var. lahrosa, Reuss. 



Cellaria lahrosa, Reuss, Foss. Polyp. "VVien Tert., p. 63, pi. vii. fig. 35. 

 HaswelUa australiensis, Busk, Zool. Chall. Exp., part xxx. p. 172, pi. xxiv. fig. 9. 



In a specimen sent to me by Mr. Haswell, from Holborn Island, the entire peristome 

 projects, whereas in the Challenger specimen it is only the proximal lip which projects. 

 The same is the case in fossil Cellaria lahrosa which I collected from the Val di Lonte, 

 in the Vicentine, and from Brendola, in the Colle Berici, Northern Italy, both of Bartonian 

 age. I hope shortly to refer more fully to these in a revision of the Italian Miocene 

 Bryozoa, upon which I am now at work. Finding the same varieties and variations of 

 mode of growth in the Australian seas and in the Miocene beds has largely influenced me 

 in uniting as synonyms Porina gracilis, Porina coronata, and Mynozoum australiense, 

 and has even influenced my. views as to the range of other species. The opercula of the 

 Challenger specimen have the muscular attachments in the same position as tho.se both 

 from Holborn Island and typical Porina gracilis, in all cases being about the same 

 size. 



The ovicells have not been described, but in my Holborn Island specimen the zoarium 

 at some whorls becomes thicker, and when sections are made the ovicell is found above 

 the peristome (PL II. fig. 8). These must be considered immersed ovicefls, as some 

 indication of their position is given externally. This is the same position and form as in 

 typical Porina gracilis. 



A further character common to both is the tubular connection from zooecium to 

 zooecium. These tubes are uniform, and resemble those leading to the exterior, and in 

 consequence there are no definite rosette plates such as we find in most Chilostomata. 

 This is much the same structure as in Myriozoum truncatum, and I have elsewhere 

 expressed the belief that this may possibly turn out to be an important classificatory 

 character. 



It will thus be seen that typical Porina coro7iata and Porina gracilis have three 

 most important characters similar and very marked. 



Adeonella jiolymorpha, Busk (PI. II. figs. 9-11, 40). 



Adeonellu polymorpha, Lusk, Zool. Chall. Exp., part xxx. p. 183, pi. xxi. figs, la, 2a, 3, 3a 

 (not figs. 1, 2). 



The young cells are elongate, with pores on the surface, often appearing as if in four 

 roffs ; the arch is then formed with, in most cases, a small avicularium at each side of 

 the bridge. In the ocecial cells the peristomial pore is frequently divided by a bar in 

 front, but this is not often the case in the other cells. In this and several other par- 

 ticulars Adeonella jwlymorpha and Adeonella intricaria are similar. The older cells 

 mo.stly have an elongate avicularium on a more or less raised mound. 



