. Bulletin of the British Museum (Natural History), Geology. THE CIRRIPEDE EUSCALPELLUM 151 Had it not been for the peduncle of E. eocenense, and those from Tierra del Fuego and Graham Land, in which they are formed entirely of separate plates, it might have been difficult to place the curiously developed peduncles from the Upper Cretaceous of New Zealand {E. zelandicum, PI. 11, figs. 1-3; PI. 12, fig. i). The outstanding features of these New Zealand peduncles are their very strong curvature, their narrow- ness and length (the largest has a length of 115-0 mm. and along the outer '^m
. Bulletin of the British Museum (Natural History), Geology. THE CIRRIPEDE EUSCALPELLUM 151 Had it not been for the peduncle of E. eocenense, and those from Tierra del Fuego and Graham Land, in which they are formed entirely of separate plates, it might have been difficult to place the curiously developed peduncles from the Upper Cretaceous of New Zealand {E. zelandicum, PI. 11, figs. 1-3; PI. 12, fig. i). The outstanding features of these New Zealand peduncles are their very strong curvature, their narrow- ness and length (the largest has a length of 115-0 mm. and along the outer '^m - ' â '"â "'^ ^xj,-^ O/^^vJ Fig. I. Euscalpellum rostratum (Darwin). Recent. Holotype. a, side view of two plates of peduncle; b, outer face of several plates; c, inner ends of several plates, x 43 diam. 195-0 mm.), their solidity, and the plates not being developed in the upper part of the peduncle. More curious still, where the plates are developed there is no sign where the peduncle is broken across, or in the transverse sections, of plates extending inwards towards the median canal, such as are seen in the peduncles of E. eocenense, E. cras- sissimum, and E. antardicum. It is evident that in E. zelandicum the projecting plates near the base are in an erect position, and except for these the peduncle is solid as far as the sub-median canal. Maybe the plates have become completely fused in the body of the peduncle. The upper comparatively smooth part of the peduncle has transverse, often wavy, and irregularly prominent growth-bands, recalling superficially a shell of the Rudist Radiolites. Anything less like Cirripede peduncles it would be difficult to imagine, but in fact that is what they are. The holotype of the Recent Euscalpellum rostratum (Darwin) is a very small form having a total length of 9-3 mm., length of capitulum 6-3 mm., and peduncle, 3-0 mm. Darwin (1851: 260) said in his description: 'Peduncle, short, about half the length of the capitulum; narrow
Size: 1502px × 1664px
Photo credit: © Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookauthorbritishmuseumnaturalhistory, bookcentury1900, bookcoll
