OF NEW SOUTH WALES. 95 



The septal apparel is always more or less distinct., never 

 completely lamellar, and formed only by a series of trabecules, 

 which constitute by their union a sort of loose and irregular 

 trellis-work. The walls present the same porous and irregular 

 structure. The visceral chambers contain at times certain rudi- 

 mentary traverses, but are never divided by floors* (planchers). 



This family of PoRiTiDiE is divided into two groups. 1. Poritin^ 

 = no cceneiichyma; 2. MoNTiPORiNyE = ccenenchyma, well developed ; 

 and it is among the 1st. group that the Microsolena are found. 

 This group contains nine genera ; the first two {Forites and 

 BJiodarcea) distinguished by pali, and the other seven (Goniopora, 

 Litharcea, Protaroea, Alveopora, Meandrarcea, Gosinarcea,) destitute 

 of those organs. 



As already stated, Microsolena is distinguished by having all 

 the individuals enclosed in a strong or compact epitheca, and the 

 septal apparatus confluent. The zoothome thus resulting is 

 massive, turbinate, gibbous, digitiform, dendroid or spread out in 

 plates. There are about twenty fossil species known, and they 

 appear as late as the later mesozoic rocks. 



The coral which I am about to describe is a Microsolena, in 

 which the septa are not confluent. It would belong to the 

 turbinate division, but must be placed in a genus by itself, for 

 the septa are not only trabecular irregular and distinct, but the 

 gemmation is most peculiar, being intracalicular and in congeries 

 of individuals, rising one above another. The walls are also entire 

 above, and form more or less complete partitions above with none 

 of that open spongy tissue which occurs in Alveopora, neither 

 could I see any of those horizontal partitions across the cells, 

 which gives to the genus just named that tabulate character of 

 the ancient Favosites.f From these peculiarities of the walls, 

 septa, and mode of gemmation, I propose the erection of a new 

 genus, to which I give the name Diechorcea (from Sceyco to stand 

 apart in allusion to the non-confluent septa). The genus 

 is thus characterized : — 



• Hist Nat. des Cor., Vol. 3, p. 172, 

 t On account of this tabulate structure, a related species of unknown locality has been 

 made the type of new genus called Favositipora by Mr. W, S. Kent (see Ann. Nat. Hist., 

 1870), but Mr. Dana h&d already called attention to the structure. 



