GENERA OE FAVOSITIDyE. 119 



Edwards, and the genus Alveolites is defined as follows (vol. ii. 

 p. 285) :— 



" Corallum stony, sometimes incrusting, sometimes free and 

 massive, formed of numerous layers which are concentrically 

 superimposed upon one another, each layer composed of tubu- 

 lar, alveolar, prismatic cellules, which are somewhat short, and 

 form a network on the surface." Four species of the genus 

 were recognised by Lamarck, of which A. suborbicularis and A. 

 escharoides have been subsequently united with one another. 

 A. viadreporacea is stated by Milne-Edwards to be a Pocillo- 

 pora, and A. incrustaus appears to be a Polyzoon. To the 

 above four species Milne- Edwards added, in the work just 

 quoted, four others, of which A. ttibiporacea and A. millc- 

 poracea appear to be referable to Favosites ; A. clavata may 

 perhaps be a Chcetetes; and A. infundibtUifera was afterwards 

 placed by Edwards and Haime in a new genus under the 

 name of RoemeiHa. 



Without taking up time by discussing the views entertained 

 as to the characters of the genus Alveolites, and the different 

 forms referable to it, by Goldfuss, De Blainville, Michelin, 

 Steininger, D'Orbigny, and other well-known palaeontologists, 

 we may pass on to consider the opinions expressed by Milne- 

 Edwards and Jules Haime in their great works on the fossil 

 corals. In the Introduction to the ' Monograph of the British 

 Fossil Corals' (Palaeontographical Society, 1850, p. Ix), these 

 distinguished authorities place the genus Alveolites in the group 

 of the Favositidae proper, characterised by the presence of well- 

 developed tabulae, the existence of mural pores, and the rudi- 

 mentary condition of the septa. They define the genus as 

 possessing a " corallum composed of superposed strata of 

 corallites very similar to those of Favosites, but much shorter, 

 and terminated by an oblique semicircular or subtriangular 

 calice, the edge of which projects on one side." The type- 

 species of the genus is A. spongites, Steininger {^=A. suborbi- 

 eularis, Lamarck). In their ' Polypiers Fossiles des Terrains 

 Paleozoiques ' (p. 254), the same authors in the succeeding year 



