lxiv 



SYNOPSIS OF GENERA. 



The structure and exacl relations of these bodies still remains open to some 

 question. As the separate plates are usually detached and isolated, it is im- 

 possible to determine how great a variation in form may have existed among 

 them in any given species, and, therefore, it may be that some of the plates 

 here described as different species on account of their diversity in form, will even- 

 tually have to be united, as being different parts of animals belonging to the same 

 species. By Woodward and Zittel these fossils are regarded as representing the 

 scaly peduncle of Lepadoid cirripedes similar to Lorkula and Archaolepas, and by 

 Barrande as an elementary type of capitulum. Figures are given by Barrande 

 and Woodward which represent the different ranges of plates constituting these 

 bodies in approximately their normal position, but in none of them is the 

 character of the distal extremity of the scaly covering represented. The type 

 specimen of the closely allied genus Strobilepis (S. spinigera) has a single 

 conical terminal plate at the distal extremity, and the entire body is probably 

 to be regarded as a capitulum, and from analogy it would appear that the view 

 of Barrande in regard to the nature of Turrilepas may be correct. 



The term Turrilepas was proposed by Woodward in 1865, the character of the 

 fossils being analysed at some length and accompanied by satisfactory illustra- 

 tion. It has, however, been customary among authors to accord recognition to 

 the term Plumulites, given by Barrande in 1872, with somewhat more extended 

 description and illustration. There seems, however, to be no valid reason why 

 Woodward's term should not be accorded acceptance. 



The genus Lepidocoleus, Faber, (Journ. Cinti. Soc. Nat. V 

 Hist.. 1886), founded upon a nearly entire specimen of 

 the Plumulites Jamesi, Hall and Whitfield, appears to be 

 composed of but two ranges of vertical plates of unequal 

 size, interlocking along their basal edges for their entire 



length. 



ft 



Lepidocoleus jamesi. 



