PALAEOZOIC CORALS AND FORAMINIFERA. 91 



phragms conspicuous. The real affinities of the genus seem to 

 be between Michelinea and Amplexus, differing from the former 

 in the tubes being individually distinct (as in Stylasiraa) and 

 easily separable by fracture, and being without communicating 

 pores ; from the latter it only differs in its compound mode of 

 growth. As thus restricted the genus is no doubt a good one : 

 the other dissimilar species placed in this genus by Dr. Goldfuss 

 and others will easily fall into Cyathophyllum and other existing 

 genera. 



Columnaria laxa (M'Coy). 



Sp. Char. Corallum forming large masses of contiguous, slightly 

 flexuous tubes, rarely in contact ; generally round and finely 

 wrinkled transversely, occasionally the tubes in some part of 

 their length touch? the adjoining ones, and then become poly- 

 gonal and longitudinally sulcated ; transverse diaphragms un- 

 dulated, and obliquely inclined in various directions ; diameter 

 of tubes from 3 to 4 lines. 



The tubes being rarely in contact, and often cylindrical and 

 flexuous, distinguishes this species from its congeners. The 

 transverse diaphragms and absence of radiating lamellse will 

 serve to separate prismatic portions from the other basaltiform 

 corals found with it. 



Not uncommon in the carboniferous limestone of Derbyshire. 



[Col. University of Cambridge.) 



Michelinea glomerata (M^Coy) . 



Sp. Char. Cells polygonal, irregularly aggregated, so as to open 

 on every side of the large amorphous masses formed by its ir- 

 regular mode of growth ; cells averaging 2 lines in diameter ; 

 internal vesicular plates very irregular, much curved and highly 

 inclined. 



This is perhaps most allied to the Russian M. concinna (Lonsd.), 

 but as that species is remarkable for the breadth, flatness and 

 horizontality of its internal plates, so this is equally remarkable 

 for their irregularity, convexity, small size, and nearly vertical 

 position, forming in the sections a multitude of small rounded 

 vesicles, without any approach to horizontality. The small size 

 of the cells and mode of growth seem somewhat analogous in 

 both, and separate them at a glance from the three other pub- 

 lished species. 



Common in the carboniferous limestone of Derbyshire, form- 

 ing subcylindrical masses 3 or 4 inches long. 



{Col. University of Cambridge.) 



