THE ANNALS 



AND 



MAGAZINE OF NATURAL HISTOEY. 



[SIXTH SERIES.] 

 No. 4. APRIL 1 



XXIX. — On the Structure o/Fistiilipora iiicrustans, Phill. 

 (F. minor, .WCoy). J3j JoiiN YoUNG, F.G.S. 



The interest excited by the researches of recent years amongst 

 the group of organisms forming the Monticuliporidaj has been 

 chiefly due to the methods now employed in obtaining a 

 knowledge of their internal structures, these being seen to 

 differ very much even in organisms that are externally so 

 alike as formerly to have been placed in the same genera or 

 species. Another point of interest in connexion with the 

 group is the doubt that still exists in the minds of many 

 palaeontologists as to their proper position in the animal king- 

 dom, one set of observers placing them along with the 

 Polyzoa or Bryozoa, another with the Actinozoa or Corals. 

 It is to be hoped that future investigations will help to clear 

 up this point and settle the question one way or other. 



In the ' Annals' for December 1882 I contributed a short 

 paper " On the Identity of Ceramopora [Berenicea) megastoma^ 

 M'Coy, with FistuUpora minor ^ M'Coy," and at p. 428 I fur- 

 ther referred to one or two external characters I had observed 

 in this organism in its several stages of growth that, so far as I 

 was then aware, had not been noticed by former observers. 

 These were : — 1st, that the mouths of the cells in the younger 

 stages are of a trilobed form, this character being due to the 



Ann. & Mag. N, Hist. Ser. 6. Vol. i. 17 



