TAMILTES AND aENERA OE THE MADREPORAEIA. 



127 



M. de Eromentel writes (' Introd. a I'etude des Polyp, foss.' 

 p. 163), " Nous avons separe des Latimeandras des fossiles qui 

 presentent bien comme celles-ci des caliees reunis en series, mais 

 dont les series restent libres par leur cote et ne sont meme pas 

 unies des cotes. Nous avons reuni les quelques especes qui 

 presentent ce caractere sous le nom generique de Chorisastrcea.'" 



Hence it is only to corals with serial calicos that Chorisas- 

 trcea can apply. 



In the Pal. Prang., Zooph. Terr. cret. p. 445, M. de Fromentel 

 states that the genus Ohorisastrcea, E. de P., 1858, includes the 

 Syrrastrseans which increase by budding, but whose series rest 

 free at the summit, and are not united dorsally or by their 

 costse. 



It is remarkable that M. de Promentel should classify Lati- 

 mcdandra with corals having serial calicos. E. Pratz has pointed 

 out that this is an error. Latimceandra has not what M. de 

 Promentel calls a Syrrastrsean type of growth, but a Disastrsean 

 or Polyastrsean (see Latimceandra Flemingi, Ed. & H.). Lati- 

 mceandrcB are modified Isastrseans ; and these last, like Lati- 

 mceandra^ often have their calicular walls separated for a short 

 distance downwards. 



Many genera have the walls united, except close to the calicos, 

 and during growth union takes place there. 



Heterogyra, Eeuss, cannot be included in the so-called genus 

 Ohorisastrcea. 1 do not think it advisable to retain this last 

 genus. 



Genus Hetekogtra, Beuss, Pal. Stud. u. die alt. tertidrsch. der 

 Alpen, Abth. i., AntJioz. v. Oastelgomlerto. "Wien, 1868, p. 20. 



Colony massive. Corallites increasing by gemmation and 

 irregular serial calicinal growth, united inferiorly, free superiorly. 

 Calicular surface irregular, showing nearly circular and very 

 deformed calicos, free from the calicinal margin down to a certain 

 depth. Septa numerous, denticulate. Columella absent. Endo- 

 theca exists, but an epitheca does not cover the costse. 



Distrilution. — Fossil. Eocene : Europe. 



The alliance of this form is with the Latimseandroids and not 

 with the Symphyllioida. Its importance is considerable in 

 relation to the so-called genus Ghorisastrcea, E. de Prom., and 

 the morphology of Latimceandra also. 



The genus Merulina was placed by Milne-Edwards and Jules 



