330 PROCEEDINGS OF THE 



of the cells, in the intervals of which they come together, or are 

 sometimes separated by one to three finer series of tubercles. The 

 tubercles on the lips of the cells are, when fully preserved, promi- 

 nent and erect. Scattered tubercles occupy the space between 

 the cells and the margin of the stem. The mesial ridge of the 

 branches is usually derived from the outer tubercular ridge 

 bordering a cell. The reverse is coarsely striated longitudinally, 

 the striae being tuberculate. 



Branches, nine; and cells eighteen, in one quarter inch on 

 either side. 



Localities: Hairmyres, E. Kilbride; Gillfoot, Carluke; Dykehead 

 Pit, Blantyre. 



The stem is somewhat flattened on the reverse, but it is doubt- 

 ful whether this is not due to pressure. In its extreme degree 

 it certainly results from crushing. The ridges vary in arrange- 

 ment; and the figures show some of these irregularities. Thus 

 (fig. 1 ) the lip of a cell is formed by a short ridge, an additional 

 one running outside of it, while in the angle (fig. 6), several 

 short ridges replace the simpler arrangement seen in other 

 specimens. 



The only described species with which this one might be com- 

 pared is G. gracilis, M'Coy (Carb. Foss. Ireland, p. 199, pi. 28, f. 5). 

 But though in that species, also, one cell intervenes between the 

 branches, the cells ai-e only " half their own length apart;" they 

 ''indent the margin strongly," and the branches have no keel: 

 strong points of contrast, even if small importance is attached to 

 the insistence on the '' circular " form of the cells. The figures 

 in M'Coy are unfortunately so artificial that they cannot be 

 depended on, since the indented margin which the text asserts to 

 be (p. 199) diagnostic from the other species, is not even suggested. 

 G. gracilis and G. flexicarinata are allied but obviously distinct 

 species, occurring in the Carboniferous Limestone series of Ireland 

 and Scotland respectively. 



GlauC'^nome retroflexa, sp. nov. 



Plate ii., Figs. 8-10. Plate iii., Figs. 11-13. 



Polyzoary erect, branches short, subalternate; bipinnate branches 

 at wide intervals. Cells on stem longer than broad, regularly alter- 

 nate, their own length apart; one at the base of each branch, and 

 one in the intervals; partly hidden on the inner side by the keel, 



