51 



, described species, the pore-like cavities only extending about half- 

 way through the theca. In looking down upon the calice, the 

 marginal portions of the uppermost row of intercostal bars can 

 be seen as an outer wall just below the summit of the internal 

 one. The bars themselves are solid, and form an integral part of 

 the solid theca of the corallum. The structure of the wall is 

 clearly indicated in a specimen from the Cape Otway section, 

 which was fractured during fossilization (PI. 11., fig. 2c). The 

 coral is not divided down the centre, but at the angle of two 

 opposite primary septa ; and the slight projection on each side of 

 the fractured surface represents the thecal connection between 

 primary and adjoining quaternary cycles of costse. Internall}^ 

 this is solid, but externally it consists merely of a series of thin 

 transverse bars. 



Height of corallum, 6 mm.; length of calice, 5*5 mm., breadth 

 of calice, 4-2 mm. The specimens vary in size, and slightly also 

 in proportionate measurements. The above dimensions refer to 

 a large one selected as type for the calice. The corallum fio-ured 

 is 5-5 mm. high. An example from Adelaide, which is fractured 

 similarly to the figured one from Cape Otway, is 5 mm. high. 



Localities. — Abundant in the earlier Eocene of Adelaide bore 

 Cape Otway, and Wilkinson's Aire Coastal Section No. 4 (types). 

 Rare in the later Eocene, west of Gellibrand River. 



The species is named after Mr. A. E. Kitson, in recognition of 

 his discovery of additional Tertiary outcrops in the vicinity of 

 the Aire River. 



Trematotroehus deelivis, spe,c. nov. Pi. ii., fig. 3a, b. 



The corallum is in outline an inverted short cone with a 

 steeply sloping surface. It is an elegant species, and by far the 

 largest of the Trematrocki. The base is sub-acute, and the calice 

 is wide, open, and slightly elliptical. The ratio of the diameters 

 of the ellipse in the type is as 100 to 89, but in another and 

 somewhat larger example this becomes 100 to 95. 



Septa in six systems, with four cycles, all of which are regu- 

 larly developed. The first two orders are stout and exsei-t 

 especially the primaries ; the tertiaries are much smaller, while 

 the quaternaries are thin and comparatively inconspicuous 

 lamina?. Some septa are occasionally notched near their central 

 terminations, but this is not a regular feature of the calice. 



The columella consists superficially of a thin, tortuous, rod-like 

 structure, with occasional projections on its surface. Offshoots 

 from it to some of the septa simulate pali, but from their 

 irregular development I judge them to be merely portions of a 

 fascicular columella. All the septa of the first and second orders 

 are fused to the columella, either by these paliform offshoots or 

 by solid processes just below its surface. 



