FOSSIL CIRRIPEDES FROM NEW ZEALAND. 845 



form an obtuse angle, the upper margin of which is straight and 

 obliquely inclined towards the apex, and the lower margin, which 

 is concave, emerges from just above the base of the valve, and 

 curves gently upwards and then sweeps sharply outwards to meet 

 the upper margin. Parietal portion of valve extremely narrow, 

 the widest part being about one-fourth the width of the widest 

 part of the ala. On the ala the growth-lines are closely set, and 

 follow a similar coui-se to those on the lateral compartment. 

 Beneath the upper half of the ala, a portion of the valve on the 

 inner surface is somewhat thickened for about one-third the 

 width of the valve ; its inner mai'gin is steep-sided, and forms a. 

 i-idge, against which abuts the angle of the alfe of the carinal 

 department ; tlie thickened portion of the valve widens gradually 

 from the apex, dies out at a point opposite the angle of the ala, 

 and is marked with fine, regular, cioselj^-set, transverse lines. 

 Near and parallel to the lower half of the parietal margin, and 

 for about one-third the width of the valve, the inner surface is 

 marked with lines which extend upwards, and, on reaching about 

 half the length of the valve, are angularly bent downwards and 

 inwards, and the lowest of them meet the base of the steep-sided 

 ridge near the upper margin of the ala ; these lines correspond 

 to, and are obviously made by, the alae of the carina, which are 

 overlapped by the portion of the valve thus marked. 



Carinal compartment (figs. 10-12) gently curved longitudinally, 

 with an ala on each side, and these are bent at a sharp angle 

 from the parietal portion. Parietal portion narrow, transversely 

 convex, especially near the apex, much narrower than the parietal 

 portion of the lateral compartment, but wider than that of the 

 carino-lateral compartment ; alae about one and a half times as 

 wide as the widest part of the parietal portion, and in one young 

 valve about the same width as the parietal portion. The alse 

 emerge from near the base of the valve, widen gradually upwai-d 

 until about two-thirds the distance from the base, and here they 

 bend further outwards and then sharply upwards to the apex ; 

 the two margins, therefoi'e, roughly form an obtuse angle, the 

 basal margin of which is somewhat concave, and the upper 

 margin, which is the shorter, is straight. The growth-lines on 

 the al£e extend obliquel}^ upwards from the base and, on reaching 

 a point more than halfway across the alae, bend shai'ply and 

 angularly downwards to the margin ; a smooth triangular portion 

 -of the valve is left beneath the angularly bent growth-lines. 

 The inner surface is quite smooth except for some transverse 

 lines, which mai'k the surface above the angle of the alte and 

 which are more prominent at this point. 



Measurements. The largest valve in the present series (a carina, 

 fig. 10) would measure, if complete, cii^ca 90 mm., and the smallest 

 valve (a lateral compartment, fig. 6) circa 12 mm. One of the 

 <!ompartments (a lateral) figured by Prof. Benham as a scutum 

 measures 187 mm. 



