116 Mr. F. A. Bathor on the 



des Crinoides du Silurien de la Boh^nie, designes par Barrande 

 sous le nom de Scyph. suhornatus^ et par nous, sous le uoms 

 de Scyph. decoraUis et Scyph. excavatus, var. Zenonis. 

 Cepeiidant la description de Scyphocr. elegans Zenker con- 

 vient parfaitement a la plupavt des specimens que nous 

 rangeons dans trois varietes nouvelles : Scyph. excavatus var. 

 typ., var. Schlotheimi, et var. Schrbter'i ; il y a nieme une 

 concordance reniarquable entre les specimens et les figures 

 donnees par Zenker." Briefly then : Scyphocrinus excavatus 

 Waagen and Jalin, non Schlotheim, is identical, even in its 

 var, typica, with S. elegans, Zenker. It seems a pity that 

 our authors did not draw the obvious conclusion, and so 

 preserve a name in universal use. Had they cliosen, " par 

 respect pour la memoire de " Schlotheim, to give the name 

 excavatus to their new species S. decoratus, none could have 

 said them nay. However, for the sake of concord, let us 

 accept the action which the authors themselves have seen fit 

 to base on their profound research. 



To the features of great morphological interest presented 

 by Scyphocrinus we can here do little more than allude. It 

 has been supposed that the peculiar network or pavement 

 which unites the proximal portions of the arms is formed of 

 modified ramuli ; but to this conception the authors do not 

 refer. The resemblance to fixed ramuli or pinnules, such as 

 are known in other genera (e.g. Uintacnnus) , is more 

 obvious in the figures of *S'. excavatus varr. typ. et Schroe- 

 teri than in those of the other varieties and species, some of 

 which represent only a solid and continuous pavement. 

 There is no geological evidence to show which is the more 

 primitive type, since, as the authors are careful to point out, 

 all the varieties are contemporaneous and associated. We 

 must turn to anatomical and comparative evidence. The 

 arms of Scyphocrinus are simpler than those of other Melo- 

 crinida", and have not the ramuli of Mariacrinus and Melo- 

 crinus. Therefore the structures in question are not so 

 likely to be modified ramuli as modified pinnules. Two 

 statements made by the authors suggest possible arguments. 

 They say (p. 72) " les brachiales de premier ordre [distal 

 secundibrachs] sont en forme de croissant ou de fer ^ cheval. 

 L'echancrure .... correspond au sillon ambulacral du fronc 

 des bras, lequel sillon jjasse dans la voute du calice." If 

 branches were given off from this ventral groove to the lines 

 of plates forming the interbrachial network, this would con- 

 firm the view that the latter were fixed pinnules. But 

 specimens examined by me, notably a fine one apparently 

 referable to Scyphocrinus excavatus var. Schlotheimi (Brit. 



