48 MADREPORARIA. 



whole surface is a confused flaky reticulum, in wliich calicles are mainly discoverable liy being 

 faint depressions. 



From the large columellar tangle groups of irregular jagged flakes rise to represent a ring 

 of pali. Approximation to the typical six can be seen, and traces of dimorphism * are visible. 



There are two specimens, a and h ; one {b, fig. 9) is a detached rounded nodule, which may 

 have been free, the greater part covered with a fresh incrustation. It is difficult to describe 

 the growth-form of «.. It appears to be a development of an explanate-encrusting stock, which 

 has risen into lobes, these swelling and dividing into thick knobs. (See PI. XI. fig. 8.) 



The calicles are all shallow, even on the tops of the knobs, S(j that the growth-form is not 

 one of those attributable to the lengthening of central caUcles (see Introduction, p. 24). But 

 though all the fossfe are shallow, there is no close return, even in the lowest calicles (fig. 9) 

 to the primitive type. 



There is considerable superficial resemblance between this coral and Goniopora Singapore 2. 

 The columnar growth of the latter is, however, much more conspicuous (see PI. XII. fig. 13 

 and p. 80), and the calicles are a trifle smaller (see PI. II. figs. 1 and 2), otherwise their general 

 appearances are the same. The most fundamental difference lies in the texture of the 

 skeleton, which in the Singapore coral is a close granulated reticulum, but this again is as 

 irregular in its way as is the open flaky reticulum of the coral here described. This resem- 

 blance receives additional importance from the fact that the locality of this specimen is not 

 above suspicion. 



That true Gonioporm occur at Samoa we gatliered from the last heading. It is possible 

 that Dr. Ortmann's G. parvistella may be more nearly allied to this than to the last form. 



a. Large stock. Zool. Dept. 1902. 9, 9. 2. 



h. A (? free) nodule. „ „ 1902. 9. 9. 3. 



Group II.— AUSTRALIA. 



Cmitainiiuj descriptions or records of Gonioporce from the Great Barrier Reef (1-12); North-West 

 Australia (1-6) ; aiid one from "Australia," hut with no nearer locality. 



!.'■). Goniopora Great Barrier Reef (i2)l. (PI. II. fig. 1 ; PL XL fig. 9.) 



[Townsville, Great P.arrier Eeef, coll. Saville-Kent ; British Museum.] 



Description. — Corallum explanate, witli smoot'n wavy upper surface, while the under 

 surface, lined with wrinkled epitheca which is thrown into deep folds, is irregularly cavernous 

 and hollow. The edges of the stock run out free, and are 2 mm. thick at the margin, which is 

 supported by epitheca, and breaks up into rounded lobes. These marginal lobes bend upwards, 



• That is, some calicles have a deep central fossa, absent in the others. See .Tonrii. Linn. 

 Soc, xxvii. (1900) p. 49G. 



