140 Scientific Proceedings, Royal Dublin Society. 
In the tables the values used are as follows :— 
I. Horizontal measure, number of columns inlom. Vertical 
measure, number of fenestrules in 1 cm. measured longitudinally. 
Il. Horizontal measure, number of tegminal openings in 1 em. 
measured longitudinally. Vertical measure, as in I. 
TII. Horizontal measure, asin II. Vertical measure, number of 
columns in | em.! 
0 
Tabulation of characteristics of specimens of Hemitrypa hibernica and H. proutana. 
1 This method of tabulating individual characters, due to Prof. Call, was brought 
into prominence by Mr. G. K Gilbert (‘‘ Special Processes of Research,’’ Amer. Journ. 
of Science, vol. xxxiii. p. 464) 
