Dr. H. Woodward— A New Cirripede from the Chalk. 147 



rafliating ribs which ornament the surface; (.3) the thickness of the 

 shell-wall ; (4) the absence of sutures. 



On turning to Dr. Rowe'.s specimen from the Margate Chalk, we 

 notice the close reseml)lance of the shell-walls (PI. VIII, Fig. 4rt, 

 c. and r.) with the Norwich example, the external surface in*both 

 being marked by strong radiating vertical costa3, crossed at regular 

 intervals by well-marked transverse rings, forming with the costse 

 a delicate reticulated ornamentation like basket-work on the surface. 

 In Dr. Rowe's specimen the opposite curved portions (r. and c.) appear 



,' / 



Fig. 1. — T'oHicipes pohjiiwrHx, G. B. SowerLy. Living-: Upper Califoruia, Pacific, 

 etc. (Alter C. Daiwiu's figure, op. cit., pi. vii, fig. 2.) " f'a])itulum with 

 two, tliree, or more whorls of valves under the rostrum ; latira regularly 

 graduated in size from the uppermost to the lowest ; scales of the peduncle 

 arranged in close whorls." The range of the genus extends from the Rhnctic 

 beds ; the Great Oolite, Stonesfield and Eyeford ; the Oxford Clay, the Gault, 

 Upper Greensand, Upper Chalk, the Eocene Tertiary, Isle of Wight ; the 

 Tertiary of Messina ; and living in tlu; seas of Europe, etc., at the present day. 



Fig. 2. — Cntnphraf/miift pobjmcrHs, Darwin. Living: Australian Coast. (.\ftcr 

 C. Darwin's figure, op. cit., j)!. xx, figs. An-Ae.) '' Interior compart nu'nts 

 eight, with several exterior whorls of small supplemental compartments ; 

 basis membranous." " In large old specimens there arc ten, or even more, 

 whorls of compartments, but it is scarcely possible to count them with any 

 accuracy." This genus does not occur in a fossil state. 



Fig. 2a. — External view of one of the imbricated scales or valves, from the second 

 whorl, counting from the inside. 



at first sight to have been forced apart, or else that two additional 

 lateral compartments of the shell-wall have fallen out and been lost ; 

 but this does not seem to have been the case. Tlio important 

 difference lies in the fact that, whereas in the Norwich specimen 

 (PI. VIII, Fig. 3) the shell-wall is exposed and bare to its basis, in 

 the Margate specimen the base is concealed by a fpiite undisturl)ed 

 semicircular quadruple row of shelly imbricated scales (PI. VIII, 

 Fig, 4a, i.s., i.s.), analogous to those at the base of the capitulum of 



