AUSTRALIAN GONIOPORA. 49 



curl round longitudinally, and, as the colony expands, appear to be left behind as blunt 

 knobs on the surface of the stock. The thickness of the colony is very irregular, from 

 1-1 • 5 cm. 



Calicles 4 mm. in diameter ; on the smooth surface open, shallow and subcirculax and 

 regular, but on the lobes and knobs drawn out of shape, sharply angular, and often deep and 

 funnel-shaped. The walls are everywhere finely reticular, thick, varying from 1 to 2 mm. 

 where thickest, flat-topped, often with the open shallow indentations of young buds. The 

 24 septa, with frilled rather than toothed edges, appear on the top of the wall, and remaining 

 very short descend nearly vertically into the calicle, where they grow out to form the typical 

 septal formula, which is sometimes visible to the naked eye. Their fusions result in the usual 

 six paliform prominences on the columella ; these prominences are lengthened out radially and 

 are large and very conspicuous ; under the lens they are seen to be raised portions of the 

 columellar tangle. The directives also frequently have minute separate paliform granules. 

 Great numbers of delicate tabulate floors begin about 2 ' 5 mm. below the surface. 



There are two specimens of this foliate Goniopore, both from the Great Barrier Eeef, 

 one (a) labelled " Townsville " and the other (b), unfortunately, only " Great Barrier Reef." 

 Their method of growth, general thickness, regular character of calicles, walls and epitheca 

 are exactly similar. In specimen (b), shown on PI. XI. fig. 9, we have a free edge, showing 

 the formation of knobs by curling lobes ; in (a) we have a completed knob rising from a 

 smooth face from which nearly all the free edges have been broken away. The only difference 

 between the two which I can detect is due to the fact that in (a) the skeletal elements seemed 

 to be a little finer than in (b); this gives a slightly different surface aspect. The septal formula 

 is less clear, and the ring of pali more irregular in (6) than in (a). Specimen (a) has been 

 bleached, but still shows faint traces of both the brown and olive-green colours which occur 

 in (b). There can be no doubt whatever that these two corals are intimately related, and, 

 I expect, came from the same locality. This is an example of the explanate growth-form 

 with persistence of the regular primitive type of calicle. Its curling-up edges, leaving knobs 

 on the surface, suggest a similar origin for the branching tufts of Goniopora Great Barrier 

 Beef 12, see p. 58. 



a. Zool. Dept. 92. 12. 1. 160. 



b. „ „ 92. 12. 1. 677. 



16. Goniopora Great Barrier Reef {12 )2. (PI. II. figs. 2-3 ; PI. XI. fig. 10.) 



[Palm Islands (almost due north of Townsville), Great Barrier Reef, coll. Saville-Kent ; 



British Museum.] 



Description. — Corallum is a thick cockscomb-like ridge with swollen, slightly lobate crest. 

 The living layer above the epitheca varies from 2 to 4 cm. deep. The thickness of the crest 

 is 3 cm. An epithecal film creeps up the sides of the crest in broad irregular strips, strongly- 

 wrinkled. 



H 



