EUKOPEAN PORITES. lU 



101. Porites Alessandria 2. (P. Alessandrina seoinda.) 



[Stazzano, near Novi- Alessandria Piedmont (Tortonian), coll. Michelotti ; Geological 



Museum, University, Rome.] 



Description. — The corallum rose into irregular, angular spikes, on columns some 3 cm. in 

 thickness. 



The calicles were 1 mm. in diameter and crowded. The walls were either single, inter- 

 rupted threads, or a reticulum, consisting seldom of more than one row of meshes. The septa 

 are twelve and show the typical formula, the directive triplet being often only partially com- 

 plete. They are thick, short, and with a tendency to swell into paliform knobs, in which 

 case a columellar tubercle may rise corresponding in thickness with the rest of the skeletal 

 elements ; or again, the septa may fuse into an open columellar ring. The skeleton is every- 

 where composed of thick, smooth trabeculae and threads ; the meshes, though sharp and 

 distinct, are small. The trabeculse, in vertical section, are slightly nodulated, radiate outwards, 

 in compact parallel bundles, with only small, irregular openings between. 



This is a typical Porites; the method of growth can be gathered from its shape and 

 especially from the fracture which shows a central region, from which the calicles start upwards 

 and outwards to different lengths. No original surface which is absolutely above suspicion 

 can be made out ; it is, consequently, impossible to say whether the calicles were superficial or 

 depressed. 



I have been permitted to examine the original specimen by the courtesy of Prof. Portes. 

 I have failed to find any other Porites very similar to it. It is quite different from the other 

 Porites from the same place described above as P. Alessandria 1. 



102. Porites Turin 1. (P. Taurinina prima.) 



[Turin (Middle Miocene) ; " and at Tortona (Upper Miocene) "]. 



Syn. " Lithareea diversiformis Mich.," Sismonda Palaeontologie du Piemont (1871) p. 25, pi. ix. 

 figs. 1, 2. 



Description. — The corallum was massive, irregularly humpy, or lobate. 



The calicles averaged 1 mm. in diameter, depressed, " but not so deep as they are broad," 

 polygonal. The twelve septa were not very crowded, though thick, and they showed hardly any 

 difference between primaries or secondaries. 



The columella was spongy. 



From the figures, which are quite clear, we gather that the walls are thin, sharp and 



