50 



Reference has also been made to this genus by Dr. Maria M 

 Ogilvie, who states that pores are present in its theca in the 

 same position as the intercostal dimples of Turhinolia, and in the 

 same position as the pores in the thecae of Turbinaria, Forites, 

 and Madrepora* But by Miss Ogilvie's scheme for the classifi 

 cation of corals, which is based on the microscopic study of the 

 skeletal features, the two families of Turbinolidse and Eupsam- 

 midse are not only placed far apart, but they are regarded as 

 sprung from separate main trunks.! Her conclusions appear to 

 be contradicted by the Australian genus under review, which, 

 with a Eupsammian-like wall, has yet certain affinities with 

 Turbinolids. 



Further consideration of the classification of Trematotrochus 

 will be best postponed till the present series of papers is com- 

 pleted. 



The species now to be described are the following : — 



Trematotpoehus Kitsoni, spec. nov. Pi. ii., tigs. 2a, 6, c. 



Corallum small, free, and compressed. It is a flattened cone 

 in shape, with a rounded, sub-acute apex. Calice shallow and 

 elliptical, with its diameters in the ratio of 100 to 75. 



Septa granular, and in six systems with four cycles, of which 

 the fourth is developed only in the end systems. In this respect 

 the coral resembles T. latcroplenus. The primaries are stout, and 

 the remaining cycles diminish in thickness according to order. 

 As a rule, the septa are free ; but, as in the type calice, some 

 may be irregularly united towards the columella by means of 

 intermediate solid tissue. Scereoplasm is also developed to some 

 extent in the interseptal loculi. 



Columella elongate, nodular at its upper surface, and almost 

 spongy inferiorly. The primary and secondary septa are fused 

 with it either directly or by means of thin processes. There are 

 no pali, but the thickened ends of some septa, chiefly the secon- 

 dary, may be regarded as paliform lobes. 



The costse, or septo-cost?e, as they may appropriately be called, 

 are minutely granular, sub-equal in thickness, and prominent on 

 the wall of the corallum. Those of the first and second orders 

 unite at the base ; just above this the secondaries are joined by 

 the tertiaries, and the latter again by the quaternaries a little 

 higher on the wall. The intercostal spaces are about equal in 

 width to the costse, and are crossed by a regular series of trans- 

 verse bars, which separate longitudinal cavities in the wall. 

 There is, however, no real penetration of this, as in the previously 



* Microscopic and Systematic Study of Madreporarian Types of Corals. 

 Phil. Trans., ser. B., vol. CLXXXVII. (1897), pp. 249 and 333. 

 tOp. cit., p. 296. 



