liia 



PALvEONlOLOGY OF iNEW-YOKK. 



509. 2. DIPLOPHYLLUM C^SPITOSUlVn 



PL. XXXIII. Fig. 2. 

 Compare Columnaria, Syringopora, Sarcinula, etc. 



The figure is drawn from a longitudinal section, and is remarkable for having the septa in 

 the middle portion of the cell bent downwards in the centre, like a series of inverted cones, and 

 presents to some extent the character of Syringopora, while the outer portion shows the fine 

 dissepiments uniting the lamellae. Notwithstanding this wide departure from the prevailing 

 character of the species, there are numerous instances of individuals approximating to this one 

 :in structure, and the external appearance presents nothing to distinguish it from those already 

 described. 



There is another fact also shown in the same specimen ; the bud on the right side of the 

 figure shows several strong transverse septa, crossing the inner division of the cell, while the 

 outer portion is distinctly separated, and of the same structure as the corresponding parts in 

 other specimens. 



It seems scarcely possible, therefore, to regard this peculiar interior structure of the main 

 stem as anything more than an abnormal development, which is to some slight extent shown 

 in the preceding sections, and which is clearly a variation in character of the same species. 

 This is the only individual, out of several hundred polished specimens, which shows this pe- 

 culiar structure. 



Position and locality. In the lower part of the Niagara limestone, associated with the pre- 

 ceding specimens figured. 



Genus SYRINGOPORA (Goldfuss). 



I have referred the following species to the Genus Syringopora, though its internal struc- 

 ture does not correspond with that given by Goldfuss. I am induced thus to refer the species, 

 from the fact that no corals have fallen under :my observation, having the structure given by 

 this author, and all those in our rocks, usually referred to Syringopora, have a lamelliferous 

 or radiate structure more or less perfect, with transverse septa or dissepiments either extending 

 across the tube or uniting the lamellae. The species from the Wenlock limestone, jeferred by 

 Lonsdale to S. reticulata of Goldfuss, has certainly a stellate structure more or less developed, 

 and the same is probably true of other species. The unequal development of the radiate cmd 

 septate characters, or their unequal preservation, has given a very variable appearance to the 

 interior structure ; and it is often altogether obliterated, and we have only external form and 

 mode of growth to rely upon. 



Should it be found necessary, on further investigation, to separate under another generic 

 name the following and allied species, the name Syringophyllum may be very properly ap- 

 plied, indicating their relation with the Cyathophyllidea. 



