W. Lonsdale on Tertiary Corals from the United States. 357 



Art. XXX. — Remarks on the Characters of several Species of 

 Tertiary Co? % als from the United- States, in reply to Mr. 

 Dana* (Extracted from a letter from W. Lonsdale, Esq. to 



C. Lyell, Esq.) 



Kynsham near Balh, June 21st, 1847. 



My Dear Lyell, — I am much indebted to you for sending me 

 additional specimens of Endopachys Maclurii. They have been 

 carefully considered ; but they have not led to a change in the 

 printed opinion; which is perhaps too briefly expressed. It 

 states that, " the Alabama coral was progressively altered in as- 

 pect, by the development of tubercles, secreted through foramina 

 connected with the internal structure." (Geol. Journ., Vol i, p. 

 >14.) This remark refers especially to a difference between En- 

 dopachys and typical species of Turbinolia, in which no forami- 

 na had been noticed in the walls, nor any external changes : but 

 in the generic characters of Endopachys, the boundary wall is 

 said to be "progressively thickened by papillee secreted from 

 within," (515,) and in a note the generic name is shown to have 

 been proposed in allusion to a " thickening from within." If 

 you will kindly examine the specimens marked 1 and 2 from 

 Claiborne, Alabama, the uppermost portions will be found to be 

 externally imperfect, and in parts, least liable to abrasion, being 

 protected by the bold ridges.f The structure in those portions 

 °f No. 1, is highly reticulated and there is apparently a perfect 

 connection throughout by means of circular openings or foramina. 

 These cancelli were evidently occupied with animal matter, 

 which was intimately connected with the soft internal living struc- 

 tures ; and which, it is believed, secreted the solid calcareous 

 reticulations. In No. 2, the analogous portions are in a more ad- 

 vanced state externally, that condition having, it is inferred, been 

 effected by secretions from the same animal tissues as built up the 

 inner part of the fabric— the foramina, which are now distinct, 



ha 



Afi 



The beautiful sections 



°f No. 2, are supposed to support the original inference. In the 

 upper part, the channels leading from the interior outwards, are 



abundan t 



terior having been perfected and the want of such passages 



finished. 



agreements betwe* 

 1 to in the notice.! 



* Silliman's Journal, ii ser., vol. i, p. 220. 



Consult also wood-cut, fig. a, p. 514, and specific characters. 

 I Geological Journal, vol. i, p. 514, olo. 



