128 On the cJiief Generic Types of Palceozoic Corals. 



there are no endothecal dissepiments, and the columella forms 

 a single styliform rod, which commences at the bottom of the 

 visceral chamber, and is continued through to the floor of the 

 calice. (It may not be out of place to note here that Gya~ 

 thaxonia Dalmani, E. & H., is not a true Cyathaxoma, but has 

 been formed into a new genus by Lindstrora under the name 

 of Centrotus.) 



The genus Loijhophyllum commences in the Devonian, but 

 attains its maximum in the Carboniferous rocks, where it dies 

 out. All the known species are small, rarely exceeding an 

 inch or an inch and a half in length. The type of the genus 

 is L. Konincki, E. & H., from the Carboniferous rocks of 

 Belgium. With the exception of a form which seems to 

 be identical with L. [Cyathopsis) eruca, M'Coy, all the ex- 

 amples figured by us (PI. VIII. figs. 3-6) are new ; but we 

 reserve the description of their specific characters till another 

 occasion. 



EXPLANATION OF PLATE VIII. 



(All the figures are drawn of the natural size.) 



Fig. 1. Dipluiphynum concinmim, Lonsd., transverse section of a small 

 slab, exhibiting calicular gemmation at dift'erent stages of the 

 process ; 1 a, longitudinal section of the same, showing the pro- 

 duction of young corallites and the continued growth of the 

 parent tubes. Lower Carboniferous, Bathgate, Linlithgowshire. 



Fig. 2. DiphyphyUum, sp., transverse section of a small slab, exhibiting 

 fissiparous development of the corallites. Lower Carboniferous, 

 Scotland. 



Fig. 3. liophophyllum pamdtim, Thomson & Nicholson, external aspect ; 



3 A, transverse section of the same. Lower Carboniferous, 

 Fifeshire. 



Fig. 4. Another example, from the Lower Carboniferous of Ayrshire ; 



4 A, transverse section of the same. 



Fig. 5. L(yphophyUwn reticulattwi, Thomson & Nicholson, external aspect ; 



5 A, ti'ansverse section of the same. Lower Carboniferous, 

 Shiels, East Kilbride. 



Fig. 6. Loj)hophyllum, sp., longitudinal section; 6a, transverse section of 

 the same. Lower Carboniferous, Shiels, East Kilbride. 



Fig. 7. LophophyUum ertica, M'Coy (?), longitudinal section ; 7 a, trans- 

 verse section of the same. Lower Carboniferous, Brocldey, near 

 Lesmahagow, Lanarkshire. 



Figs. 8-8 b belong to the next portion of this memoir, where their cha- 

 racters wiU be discussed. 



[To be continued.] 



