Dr. H. Woodward — Cirripede& from Trimmingham Chalk. 353 



which is unlike any of those already noticed. In general form this 

 valve resembles the tergum of S. arcuatum from the Gault of 

 Folkestone ; it may also be compared with that of S. solidulum from 

 Scania ; in all three terga the ornamentation consists of a series of 

 longitudinal raised lines diverging from the apex of the valve at 

 unequal distances apart, some being relatively finer than the others. 

 In S. arcuatum the main ridge, passing down the centre of the valve 

 from the apex to the basal extremity, is grooved, whereas in the 

 specimen before us the valve has a well-defined rounded ridge. The 

 radial longitudinal lines on the carinal side of the ridge are 

 extremely fine, and broader and stronger on the outer half of the 

 valve than on the inner side of the main ridge. The occludent 

 margin has a strongly raised border, followed by a wide groove 

 extending from the apex to the scutal margin. The lines of growth 

 are most strongly marked on the occludent margin, but they can be 

 faintly seen over the whole valve. On the inner side of the valve 

 the apex (more particularly on the carinal margin) becomes greatly 

 thickened. 



Extreme length of valve, 24 mm. ; extreme breadth, 13 mm. ; length 

 of occludent margin, 16 mm. ; of the carinal margin, 13 mm.; and of 

 the carino-lateral margin, 15 mm. The scutal margin is convex ; the 

 carino-lateral margin forms an obtuse angle, the sides of which are 

 straight ; the occludent margin is very slightly concave. 



The two valves already noticed from Mr. Brydone's collection of 

 Trimmingham Cirripedes, under the tentative name of P. concinna, 

 are the only two other valves in the collection having a similar 

 ornamentation of finely radiating longitudinal lines, but we have no 

 other grounds for associating these detached valves together. 

 Dr. Eovve's (as already stated) being from an entirely difierent 

 locality and horizon (?) in the Chalk. 



11. Bkachylepas (?), sp. (Figs. 38, 39.) 



Latera (Figs.38and39). — We give two views of a remarkable form 

 of detached latus, but it is uncertain to what species of Cirripede it 

 belonged. This is a narrow, elongated, irregular valve, and but for 

 the fact that it is extremely solid it might readily be overlooked and 

 thrown aside as merely part of a very narrow-valved Ostrea. There 

 are in all five specimens from the Trimmingham Chalk, having the 

 same ornamentation as shown in the figured example. Two of these 

 are from Mr. Clement Reid's collection, and three from that of 

 Mr. Brydone. There are three other fragments not quite so robust 

 and having a distinctly V-shaped ornament similar to that on the 

 carina of Scalpellmn maximum, and possibly they were latera of that 

 species. Length of figured specimen, 22 mm. ; greatest breadth, 

 5 mm. ; greatest thickness, 6 mm. 



Similarly-formed latera occur in £racJiylepas fallax (Figs. 21, 22, 

 p. 344) ; also in the recent Pollicipes mitella (see Fig. B, ante, 

 p. 340, I) and many others. 



nECADE V. — VOL. III. — NO. VIII. 23 



