^^^- 55-] BEDDED ROCKS OF COTJNTT WATERFOED. 751 



cheek, and therefore some further notes on the species may he given 

 here. 



The posterior outer portion of the fixed cheek is much produced 

 laterally, and the posterior border of the cheek curves steadily 

 backward to the genal angle, which is bent downward and pro- 

 duced into a rounded spine that has been broken off short, but is 

 most distinct. This is a most uncommon, if not unique, feature 

 in the genus. 



The eye-ridge runs at right angles to the axial furrow, from the 

 level of the anterior glabella-furrow to the base of the long stalk- 

 like eye-lobe, which is situated at a distance from the axial furrow 

 about equal to the width of the glabella, and is directed obliquely 

 forward, outward, and upward. 



There are three large tubercles on the fixed cheek, the inner two 

 being in a line parallel with the axial furrow. 



Measuremeistts. 



mm. 



Length of eye-ridge , 6'0 



„ ,, eye-lobe stalk 40 



„ ,, fixed cheek from the eye-i-idge to the posterior margin ... 9*0 

 Width of fixed cheek, measured obliquely from the base of the eye- 

 ridge to the genal spine 16"0 



Cybele McHenrti, sp. nov. (PI. XLIX, fig. 7.) 



Head-shield semilunar, twice as broad as long, slightly convex, 

 and arched from side to side. Genal angles rounded. 



The glabella occupies about the middle fifth of the breadth of the 

 head-shield, is cylindrical, nearly parallel-sided, gently convex, rising 

 highest in the centre between the first pair of lateral lobes. The 

 anterior end is obtusely pointed. The length is about one and a 

 half times the breadth. The central portion of the glabella is 

 marked off, and swells up between the lateral lobes, rising above 

 them, so that the glabella appears divided into a median raised 

 and two depressed lateral portions. Straight, almost parallel axial 

 furrows mark off the glabella on each side and curve round its 

 anterior end, defining there a narrow depressed border bearing 

 a row of marginal tubercles along its outer edge. The sides of 

 the glabella are marked by three pairs of strong, short, lateral 

 furrows, slightly oblique, and rather less in length than one-third 

 of the width of the glabella. The two posterior pairs of furrows 

 are of equal depth along all their length, and are nearly at right 

 angles to the axial furrows. The anterior pair is rather less deep, 

 but more oblique to the axial furrows. 



The basal lateral lobes and second pair are of equal size, but the 

 first (anterior) pair is rather larger and more swollen, though less 

 sharply defined. 



The frontal lobe is large, more than one-third of the length of the 

 glabella, obtusely pointed in front, and with obtuse lateral angles, 

 opposite which is the usual pair of deep lateral pits at the anterior 

 ends of the axial furrows. 



