322 1\ H. Withers — The Cirripede Brachylepas cretacea. 



H. Woodward (1865) called attention to a valve from the Chalk of Norwich, 

 which he considered to be a jjortion of the shell of a sessile Cirripede belonging 

 to the genus Pyrgoma, and for which he proposed the name P. cretacea. This 

 valve, discovered by the late T. G. Bayfield, of Norwich, was subsequently fully 

 described and figured by Dr. H. Woodward in 1868. 



J. I. Lahusen (1873) described and figured as beaks of a Nautilus, two valves, 

 a carina, and rostrum, from the White Chalk of Simbirsk, Russia. He figured 

 also, as Pollicipes sp., some valves associated on the same j)iece of chalk, 

 consisting of a nearly complete scutum, and what appear to be portions of 

 two terga. 



Th. Marsson (1880) described and figured under the name Pollicipes canccllatus 

 a valve of this Cirripede, which he said was not uncommon in the Chalk of 

 Eiigen, is easily recognizable, and not to be confused with any other Cirripede. 

 He described and figured the carina only, but mentioned that he had recognized 

 parts of latera, and probably an upper latus, and j)art of a tergum. These, 

 however, were said to be too incomplete to permit of the reconstruction of the 

 form of the valves. 



W. Dames (1881) in a review of Marsson's paper, said that valves of 

 P. cancellatus were not uncommon in the Chalk of Limeburg, and had also 

 been described by J. I. Lahusen (1873) as beaks of a Nautilus, from the White 

 Chalk of Simbirsk, Russia. 



F. A. Quenstedt (1883) figured a valve, probably a rostrum, and said that 

 smooth and very broad carinal valves occurred in the White Chalk of Liineburg, 

 and that these might aj)propriately be named Pollicipes Iccvissimus. 



K. A. Zittel (1885) in his Handbiich der Palaeontologie, figured a series 

 of valves from the Upper Chalk of Liineburg without descriptioir under the 

 name P. Icevissimus, Quenstedt. These valves are respectively called "carina, 

 ? rostrum, scutum, tergum, and lower latera". There are three lower latera, 

 but no upper latus. 



H. Woodward (1901) in a further paper on ' Pijrgoma cretacea ' added much 

 to our knowledge of this species, through the discovery by Dr. A. W. Rowe of 

 a remarkable specimen from the Belemnitella vmcronata-7,onQ of Norwich. 

 This fossil consisted of the carina and rostrum, which were kept in position 

 through the presence of three or four whorls of imbricating plates round the 

 base of the capitulum. From a study of this new specimen of ' Pyrgoma, 

 cretacea ', Dr. Woodward concluded that it would have to be removed from the 

 genus Pyrgoma, and he based on it the genus Brachylepas and the family 

 Brachylepadidae. He remarked on the absence of the remaining valves, but 

 did not refer to the valves already figured by Zittel (1885). He thought also 

 that scuta, terga, and perhajjs a small and narrow latus, completed the 

 capitulum, and he represented these valves diagrammatically in a restoration. 



A. Wolleman (1902) noticed some valves from the Belemnitella viucronata- 

 zone of Liineburg, and referred them to Pollicipes cancellatus, Marsson. 

 He suggested also that the valves figured by Zittel (1885) as P. Icevissimus 

 were probably worn valves of P. cancellatus. 



H. Woodward (1906) remarking on a specimen of Brachylepias cretacea, 

 collected by Mr. E. M. Brydone in the Chalk of Trimingham, said : "A careful 

 comparison of Mr. Brydone's specimen with Dr. Marsson's figure on the one 

 hand and with the long series of specimens obtained by Dr. Rowe from the 

 Chalk of Catton, near Norwich, leaves no doubt in my mind that Pollicipes 

 cancellatus, Marsson, is identical with Brachylepas (Pyrgoma) cretacea, 

 H. Woodward, 1868, so that Pollicijycs cancellatus must be treated as 

 a synonym of Brachylepas cretacea.''^ 



J. Boehm (1906) called attention to a shell-fragment from the Upper Senonian 

 of Haldem, preserved in the Geologisches Landesmuseum of Berlin, and said that 

 it agreed exactly in form and sculpture with H. Woodward's figure of Brachylepas 

 cretacea (1901, PI. VIII, Fig. 4), except that the ribs were thinner and 

 sharper, just as they were in Fig. 4a. He said also that the fossil described by 

 Hebert (1855) as Emarginula i?) Naissanti was distinguished from the preceding 

 only by its smaller size, and that if it should be found to be a young stage of 

 B. cretacea, then this form would have to be known as B. Naissanti, Hebert, sp. 



