132 REPORT— 1871. 



Columnaria is a fine form ; the great septa (12 to 18) and tabulae, with 

 the compact walls, distinguish it at once. Col. alveolata is a Lower SHuriau 

 form, C GotMandka is Upper Silurian. It is a most important genus, and 

 its affinities will be noticed. 



The Favositidse have a massive corallum without ccenenchyma, septa, and 

 perforate walls ; that is, there are openings which permit the visceral cavity 

 of one coraUite to communicate with that of another in several places. The 

 foUovsdng genera are included by MM. Milne-Edwards and Jules Haime : — 

 Favosites, Emmonsia, MicJielinia, Roemeria, Koninchia, Alveolites. 



Favosites is the typical genus. In some species the mural foramina are 

 scanty in number, in others numerous ; and they are even in relation with 

 the angles of the wall, especially in F. alveolar is. 



The earliest species of the genus are Lower Silurian, for instance : — F. Qoth- 

 landica, F. multipora, F. aspera, F. Forbesi (which ranges through to the 

 Upper Silurian), and F. fibrosa (having the same vertical range, and is found 

 as a Devonian fossil). 



F. Hisingeri has the same range as F. fibrosa. F. cristata and F. cervi^ 

 cornis are the same, and the range is from the Upi^er Silurian of England 

 to the Devonian of Russia. 



The species which are Devonian, and do not range above or below, are : — 

 F. Goldfussi, F. basaltica, F. polymorp'ha, F, alveolaris, F. pedicidata, F. Tclii- 

 TiatcheJJi, and F. niammillaris. The only known Carboniferous Favosites is 

 F. parasitica, and it is a degenerate form. 



F. Oothlandica has rounded processes encircling the mural pores, and the 

 projections formed upon one fit against those of the neighbouring corallite. 

 F. multipara has three vertical series of pores, and its walls are almost as per- 

 forate as some Alveoporte. 



The tabulae are almost universally horizontal in the lavosites, but some are 

 wavy in their course ; and the septa are a series of vertical spines which vary 

 in size according to the cycle, and are often referable to three cycles in six 

 systems. In some there is a faint columellary swelling on the tabula?. 



A careful examination of the species proves that the earliest known forms 

 are as highly developed as the Devonian, but that the sj^eciea parasitica is 

 dwarfed. 



Emmonsia has imperfect tabula;. The tabulae are vesicular at the sides, 

 or dissepimental, and they communicate more or less with each other. 

 Roemeria has infundibuhform tabulas, and the species is Devonian. 

 Koninckia is an Upper Cretaceous form ; it has thin and nearly horizontal 

 tabulae, thiu walls very much perforated, and six series of large spiny septa. 

 Michelinia has irregular and vesicidar (dissepimental) tabulae, and simple 

 striae for septa (Devonian and Carboniferous). The alliance of Michelinia, 

 Roemeria, and Emmonsia is very evident. Mr. Kent has written a most 

 interesting description of Favositipora (Kent), Ann. & Mag. Nat. Hist. 1870, 

 vol. vi. p. 384, which unites the Favositiuae and the Favositidae. 



Alveolites ofi'ers the same objection to being united to i^rtvosjV^s that Cten? to 

 does to PociJlopora ; in fact Alveolites is a Coenites with perforated walls, 

 and it is proposed to deal with both genera by disassociating them from their 

 recognized families. 



Biiringopora I propose uniting with the Favositida?, as it has tubular 

 connexions between the visceral centres of the corallites, which are fore- 

 shadowed in F. Gotldandica. 



After this analysis of the TabiJata, it is necessary to state the opinions of 

 Prof. Agassiz respecting their Hydrozoau characteristics. 



