170 
G. TV. Lee — Trepostomata. 
Comparable species. —The tenuity of the peripheral end of the walls is a character 
which occurs in one only of the other known species of Section A of Tabulipora , namely 
T. maeandria sp. nov., a species agreeing closely in its internal structure, but exhibiting 
a most unusual mode of growth. 
Observations. —The sections figured, pi. xv., figs. 26, 27, are from one of the 
Ravenstonedale specimens in the Nicholson Collection, while fig. 25 is from the Lowick 
specimen [25571], preserved in the Collections of the Geological Survey in London. 
fUlC-7 &UA -U 1** f’tj . v4 ^ 
Tabulipora maeandria sp. nov. 
Plate NY, figs. 28, 29. 
Description. —(a.) External characters. The type consists of an irregular mass, 
40 mm. long, some 25 mm. in width, and 13 mm. thick, composed of zooecia attached to 
an epizoarium which is repeatedly folded upon itself. Where the lower surface of the 
epizoarium is exposed, it is seen to be wrinkled. 
(b.) Internal characters. The proximal end of the zooecia is nearly parallel to the 
epizoarium, the distal end being at right angles. The wails are thin throughout, with a 
few slender, but distinct swellings in the distal region, which attains 5 mm. in length. 
Owing to the thinness of the walls, the zooecia have a polygonal section. The tabulae 
are separated by intervals which can be less than their own diameter, and bear a small 
subcentral perforation. A small acanthopore can be seen at the junction-angles. There 
are some forty-five zooecia along a distance of 1 cm. 
Distribution. —The type, and two or three specimens probably conspecific with it, 
were collected by Mr. J. Smith from the white limestone of Poolvash, Isle of Man. 
Comparable species. —The similarity between the internal structure of Tabtdipora 
tenuimuralis and that of T. maeandria has already been noted. Were future investigations 
to disclose the existence of the former as offshoots attached to the latter, then the two 
species could be united, if the peripheral region of T. tenuimuralis were shown to 
attain the length it has in T. maeandria. An analogous mode of growth is exhibited in 
a specimen preserved in the Collections of the Geological Survey of Ireland. It is 
fragmentary, but judging from its shape, it must have belonged to a mass of considerable 
size, not unlike Stenopora crinita Lonsdale, as figured by Mr. R. Etheridge. 1 The zooecia 
are much larger than in T. maeandria , and the appearance of the casts seems to show 
7, pi. ii. 
