3 



excellent figures given by Moseley of the two new species dredged 

 by the Challenger may also be referred to as illustrations of the 

 variability in the septal arrangement observed in forms belonging 

 to the genus. "^ 



Desmophyllum Joannense, ^7>ec. nor. Pi. i., figs. 2a, b. 



One specimen only has been found, but it is well preserved. 

 It is irregularly cornute in form, and gently tapering. Its basal 

 extremity is not perfect, and I judge has been sharply broken off 

 •from its former attachment to a foreign body. The calice is open, 

 much indented marginally, and slightly elliptical, the ratio of 

 its major and minor axes l3eing as 100 to 90. 



Septa in eight systems and three cycles, of which the third is 

 absent in two of the systems. The primaries are exsert, and, 

 though unequal in size among themselves, are usually much 

 stouter than the remaining orders. The secondaries and tertiaries 

 also vary in size. One of the primaries, as shown in the drawing 

 (PL i., fig. '2b), is formed of two uniting lamelke. The total 

 number of septa is 30, all of which project slightly beyond the 

 wall. The latter is thin, and covered with a white, delicate 

 epitheca, beneath which the costae can be faintly traced as rows 

 of very tine granules ; they are apparently continuations of the 

 septa. The epitheca is occasionally slightly wrinkled, and there 

 are two or three small excrescences on the wall. There is no 

 columella, and the central fossula is very deep. 



Height of corallum, 13-5 mm.; diameters of calice, 5-25 and 

 4-75 mm. 



Locality. — Eocene at Brown's Creek, near Joanna River, on 

 ^he south coast of Victoria. 



The third coral under notice in the present paper has been 

 -hitherto regarded as a variety of Deltocyathus viola, Duncan, 

 from which it differs principally in being slightly instead of much 

 compressed. It is, moreover, a restricted form, having, so far, 

 been reported from Spring Creek only. Before describing it 

 some remarks upon the generic position of its close ally, D. viola, 

 are necessary. 



In 1860 Tenison-Woods sent this species, under the name of 

 Turhinolia viola, to Professor M. Duncan, who in describing it, 

 first in 1864,* and again in 1870,t changed the genus to Caryo- 

 phyllia. Subsequently Woods redescribed it as a Deltocyathus, 

 at the same time giving a detailed diagnosis, which differs some- 

 what from that contained in Duncan's memoirs. | Afterwards, 



*|Reporton Corals — Deep Sea Madreporaria, pp. 160-2, plates iv., v., vi. 

 t Ann. and Mag. Nat. Hist., third series, 1864, p. 162, pi. v., fig. 1. 

 JQ.J.G.S., vol XXVI., pp. 295-6, pi. xix., fig. 1. 

 §Proc. Roy Soc, New S. Wales, 1877, pp. 191-2, pi. ii., fig. 3. 



