Observations in reply to Mr. Lonsdale's "Remarks." 361 



There seems therefore to be reason for dissenting from Mr. 

 Lonsdale, as to the importance of the characteristic upon which 



he has established his genus. 



Madrepora tubulata. — The genus Madrepora, characterized by 

 an apical polvp to each branch, graduates into Manopora (D.), 

 when the distinction of apical polyp is lost. The latter are folia- 

 ceous and glomerate species having the cell of the Madrepor&s in 

 every particular, but with irregular calicles or none ; they include 

 the species of the genus Montipora of Blainville, based on the 

 existence of warty prominences over the corallum between the 

 cells, (a character without importance and of impracticable appli- 

 cation;) and also a part of the Pontes of Lamark, (Porites spu- 

 mosa, &c. ) And as the transition is very gradual there are inter- 

 mediate species, two or three of which I have referred to Madre- 

 pora, since they have regular calicles although the apical polyp 

 cannot be distinguished.* But the structure of Oculina is in no 

 respect represented or approximated to. Indeed the mode of bud- 

 ding of this genus, allies it more nearly to the Astaea family, in 

 which certain branching species show the alternate gemmation at 

 apex characterizing Oculina. Hence the species referred to is far 

 removed from Madrepora ; and if it be not an Oculina (by having 

 but twelve lamellae, and twelve tentacles to the polyps) it must 

 either belong to a new genus, or else the characters of Oculina 

 should be so extended as to include it. I have been long con- 

 vinced that the number 12, has been allowed too much authority, 

 and have so far infringed upon it in my treatise on Zoophytes as 

 to unite the genera Porites and Goniopora into a single family. 



But from Mr. Lonsdale's figure, it is evident that the animal 

 had normally more than 12 tentacles, and that the lamella? are 

 fe ut 12 in number because part are obsolete. The striae around 

 *e cell are a more correct indication of the character of the ani- 



ttal, than the lamellae alone. 



(Mich 



These species are still more ambiguous cases, about which 

 there maybe an honorable difference of opinion. Having exam- 

 ined ihe corals referred to, I came to the conclusion, which I 

 still hold, that in one essential character, the species are rather 

 allied to the Caryophyllia family, than the Astr&ea ; notwithstand- 



• It is interesting to trace the transitions between these_ gener »• '" ^'^ ^ 

 «he horizontally growing species, form « »ri«, m which the b™ncbe, an more 

 »nd more coalescing till at last they form a solid plate, W'tf™">l™%. "fa" 

 »ly here and there show the tips of the branches of wh.ch .1 is composed ne 

 »?« step beyond this, is an absence wholly of the branchlets, and I the pec.es ^ a 

 «Ve leaf or folium growing at margin. In all ^own spec.es when Uus* ep .■ 

 **ehed, the cahcles are very imperfect or want.ng, and they a ^f^i which 

 ^e same manner other Madrepores pass into spec.es with stou br ^. '"• '"^'j ' „" 

 'he terminal polyp is hardly distinguishable (M cuneata an. l ^ f>™^™ Vom 

 n tf *t 8 ,ep i s a l glomerate Manopora. Thus there are two lines of gradation trom 



Madrepora into Manopora. 

 Second Series, Vol. IV, No- 12—Nov., 1847. 46 



