G. W. Lee — Trepostomata. 173 
(b.) Internal structure. The. peripheral part of the zooecia is short and somewhat 
oblique relatively to the long axis of the zoarium. In that portion of their course 
the walls are very thick. In the type-specimen they do not show moniliform structure. 
The tabulae are scarce—at most five to each zooecium—and extend only half-way 
across the cavity. Tangential sections near the surface show that the acanthopores are of 
two sizes : larger ones occupy the junction-angles while numerous minute ones encircle 
the zooecia. 
Distribution. —The original of pi. xvi., figs. 5 and 6. was collected by Mr. E. Dixon 
150 yards S.E. of Stackpole Quay Farm, Stackpole, from beds belonging probably to the 
C zone of the Lower Carboniferous [E. D. 998]. A specimen differing from the type in 
having slightly moniliform walls, was found at Blucks Pool, S. end of Freshwater West, 
Pembrokeshire, in beds belonging to the top portion of the Tournaisian [E. D. 1750]. 
Comparable species. —The last mentioned specimen seems to be intermediate between 
the type and- two forms in which the peripheral end of the walls is thinner and more 
distinctly moniliform, thus suggesting affinities to T. sparsiiabulata. One of these 
[E. D. 995] occurs with the type at Stackpole ; the other comes from The Wash, 
Castlemartin, and belongs probably to the Syringothyris Zone. 
A specimen collected on the English side of Penton Bridge, Cumberland, from a bed 
characterised by the typical form of Productus giganteus (Mart.), has, like T. crassimuralis , 
thick unbeaded walls, but the peripheral end of the tubes being longer it may equally 
well be considered as bearing affinities to T. sparsitabulata. 
Tabulipora multitabulata sp. nov. 
Plate XVI, figs. 3, 4. 
Description.— (a.) External characters. In the specimens that have come under 
observation, the zoarium consists of solid cylindrical dichotomous branches from 4 to 
7 mm. thick. The apertures number about 60 along a distance of 1 cm. Their outline 
is circular and the partitions are rather thick. An aperture smaller than the average is 
frequently interpolated between the main ones. By means of a strong lens a row of 
acanthopores can be seen encircling the zooecia. 
(b.) Interned structure. The peripheral part of the zooecia is long and at right 
■angles to the long axis of the zoarium. In that portion of their course the walls are as 
thick as, or thicker than the diameter of the enclosed zocecial cavity, and afford a slight 
suggestion of moniliform structure. 
