T. E. Withers— Cirripedes from the Chalk. 27 



the apex ; and probably projected freely to some extent. The lines of growth are 

 directed upwards from the middle of the carina, where they are obtusely V-shaped, 

 and then curve downwards to the inner margin of the parietes, whence they are 

 abruptly and obliquely inclined towards the apex. The whole exterior surface is 

 ornamented with fine, rounded, longitudinal ridges, which are finer and more 

 numerous near the inner margin of the valve. 1 



Comparison ivith other Species. The carina described by Darwin 

 as Pollicipes striates (1851, p. 70, pi. iv, fig. 5) agrees with P.filosus 

 in being longitudinally ridged, but disagrees in being plainly 

 carinate, and the longitudinal ridges are not so fine, rounded, or so 

 closely set. P. filosus is also strongly convex in transverse section, 

 while P. striatus is flatly arched and almost triangular. P. jilosus 

 may be compared with the carina of P. glaber, F. A. Eoemer (1841, 

 p. 104, pi. xvi, fig. 11), and the two carinas doubtfully referred by 

 Darwin (1851, p. 58) to his P. Angelini. These latter valves, 

 originally in the Fitch Collection, are now preserved in the Norwich 

 Museum. Both in P. glaber and P. Angelini the direction of the 

 growth-lines almost exactly agree with P. filosus, and consequently 

 the three species have their basi-lateral angles produced into short 

 spurs. They differ from P.filosus in being much wider and shorter, 

 plainly sub-carinated, flatly arched transversely, and in their surface 

 not being covered with numerous fine longitudinal ridges. One of the 

 two carinas referred by Darwin to his P. Angelini agrees more closely 

 than the other with P.filosus in the direction of the growth-lines, and 

 this specimen has a few flattened longitudinal ridges near its apex ; 

 but the rest of the valve is smooth, and differs in the characters 

 mentioned above. 



Lokicula expansa, sp. nov. Pig. 8. 



Diagnosis. Scutum smooth, slightly longer than wide, with the 

 umbo situated nearly in the middle of the occludent margin, and 

 a single well-marked groove extending from the umbo to near the top 

 of the tergo-lateral margin. 



Material. Two left and three right scuta, all nearly perfect. The 

 complete left scutum, which is the largest, measures 7 mm. in length 

 and 5 mm. in breadth. 



Holotype. The left scutum (Fig. 8). 



Horizon and Locality. Upper Senonian, Actinocamax qnadratus- 

 zone : East Harnham, near Salisbury, Wilts. 



Description of Holotype. Left scutum sub -triangular in general outline, extremely 

 thin, slightly convex ; occludent margin slightly rounded in its upper part, dropping 

 rapidly down in an almost straight line to the rostral angle, the lower part of the 

 occludent margin being almost at right angles to the basal margin ; the upper part of 

 the occludent margin suddenly rises up from a groove, which extends from the umbo 

 to near the top of the tergo-lateral margin ; basal margin straight, almost at right 



1 Since writing the above description, I have been shown by Dr. H. "Woodward 

 some Cirripede remains from the collection of Mr. R. M. Brydone, F.G.S. Among 

 the specimens are two portions of carina? of Pollicipes filosus, together with a tergum 

 which, judging from its ornamentation, also belongs to P.filosus. These specimens 

 came from the Belemnitella mucronata-zone of Portsdown, Hants. One of the 

 portions of carina? represents the upper half of a valve about the same size as that of 

 the holotype. It agrees exactly in its external form and ornamentation, but the 

 upper portion is much more solid, and the character of its inner surface shows that 

 the valve must have freely projected for about one-fourth of its length. 



