THE SESSILE BARNACLES. 277 



1825. Polylepas (Cciopirus) vulgaris Guay, Aunals of Philosophy, new 



ser., voL 10, p. 105, based upon Curomda halaiiaris Laiuaix-k, Xot 



DUuUina vulgaris Schumacher, 1S17. 

 1848. Coronula hahowris Lamarck, Kkauss, Die Siidafrikaiiischeu ;Mo11us- 



ken, p. 135 (Table Baj'). 

 . Coronula halwnaris Chenu, Illustrations Couchyliologiques, pi. 2, 



figs. 1, 4 ; pi. 3, figs. 1-A. 

 1852. Cetcopirus couiplanatus Chemnitz, ^Mouch, Catalogus Conchyliorum, 



Comes de Yohli, p. 67. 

 1854. Coronula hala:naris Dakwin, Jlonograph, p. 415, pL 15, figs. 2-2^; 



pL IG, figs. 3, 5. 

 1910. Coronula darimni Stebbing, Annals of the South African Museum, 



vol. 6, pi. 4, p. 572, bas(Hl upon C. haJwnaris Darwin. 



Distribution. — Amboina (Rumphiiis) ; New South Wales (Dar- 

 win) ; South Africa (Kraiiss, Darwin) ; AVest Africa and Valparaiso 

 (U. S. N. M.) ; Coqiiimbo and coast of Norway (Paris Museum). 



C. coTThplanata differs from tlie other recent species by the broad 

 base of the bod3^-chamber and the very thick radii, in which the beau- 

 tifully laminate edge covers ahnost the whole sectional area of the 

 compartment, while in the others the laminate edge is restricted, and 

 there is a hollow below it occupied by branches of the ovaries. (See 

 pi. 63, figs. 3, 3a) . The terminal flanges of the parietal ribs do not have 

 crenulated edges. The parietal ribs bordering the sutures seen in the 

 base bear several branches in large specimens, usually s}^mmetrical on 

 the two sides of each suture, having a tree-like or candela1)ral appear- 

 ance ; the two intermediate ribs of each compartment being simple or 

 forking near the end. Externally the ribs are flattened and subdi- 

 vided. Near the periphery they are crossed by narrow close wrinkles, 

 which are beaded b}^ the fine radial stripe. The contour varies, but I 

 believe it is rarely if ever so high as the lowest C. diadema. 



Greatest diameter 74 mm, ; height 28 mm. 



Greatest diameter 53 i mm. ; height 12 mm. 



Greatest diameter 33 mm. ; height li mm. (compressed young speci- 

 men). 



The scuta are contiguous, small ; terga much smaller. 



I have seen a consideralile series of this species, but only three lots 

 bear locality data. One in the collection of the Academy of Natural 

 Sciences, Philadelphia, is labeled California, but as it was purchased 

 in London many years ago, the label is probably apocryphal. One 

 of the lots in the United States National jNIuseum is labeled West 

 Africa, and another is in a box with the label Valparaiso, but these 

 specimens have been in the collection many years, and the collector 

 is not stated. I can not find that any definite records have been pub- 

 lished since Darwin's Monograph, except those given by Gruvel for 

 specimens in the Paris Museum, from collectors of the first half of the 

 last century. 



4729°— Bull. 93—16 19 



