328 PROCEEDINGS OF THE 



Variety a: spinosa. Figs. 9, 10, pi. xl. op. cit show strong 

 tuberculation, the intervals being smooth; and fig. 11 shows these 

 tubercles as almost spines. Where they are abraded, a central pit 

 is suggested by the unequal wearing of the denser outer and softer 

 central tissue. 



The branches present three modifications: they are short and 

 poriferous, they bear cells on the sides, and terminate with blunt 

 ends; or they have (fig. 5 op. cit.) two terminal cells close 

 together, the branch being probably continued past the cells by 

 outgrowth of the axis between them. 



Localities: Limestone shales at Hairmyres, Eobroyston, Gare, 

 and Boghead. 



Glauconome elegans, sp. nov. 

 Plate iv., Figs. 27-32. 



Polyzoary erect, slender, bipinnately branching. Stem rounded, 

 mesial ridge broad, low; the poriferous and non-poriferous faces 

 unequal, the cells and branches being turned towards the former. 

 Cells alternate, equidistant; upper margin more prominent than 

 the lateral, which sink away into the general surface below. The 

 orifice is circular when entire, or pyriform. The middle line 

 bears nearly equidistant small tubercles — one for every three cells. 

 The reverse is flattened and striated longitudinally, the stride being 

 covered with close-set fine tubercles. The branches are opposite, 

 or sub-alternate; the average angle of divergence is 35". The 

 cells are similar, as to size, distance, form, and alternation, to those 

 of the stem; but two or three lines of approximately parallel 

 ridges give a carinate aspect to the obverse, while the tuberculate 

 ridges of the reverse are bolder and more regular than those of the 

 stem. Seven branches and twenty-one cells in one quarter of an 

 inch on either side. The intercellular space is ornamented with 

 four or five finely granulated ridges. 



Locality: Upper Limestone shales, Hairmyres, East Kilbride. 



Tlie striate condition of the intercellular area on the stem, and 

 the inequality of the two surfaces, are the most distinctive 

 characters of this species, which is further separated from G. 

 gracilis, M'Coy, by having two pores, not one, in the intervals of 

 the branches. The plane of tlie apertures being parallel to that of 

 the poriferous face, and the bending of the branches towards that 

 face, are points of contrast to G. retroflcxa, nobis, hereafter to be 



