274 PROCEEDINGS OF THE ACADEMY OF [1881. 



1878. (?) Stelidiocr. ovalis AnKclin. Iconogr. Grin. Suec, p. 21, I'l. ID, fig. 6. 

 Upper Silur. Gothland, Sweden. 

 This species differs from Stelidiocrinm in several important points and ought 

 to be separated from it. To judge from the construction of the anal plates 

 it should be removed to the Agaricocrinites, but it is possible, if the figure 

 is correct, and the interradial plates, as there represented, extend to the 

 basals in all five areae, that it possesses underbasals, and properly belongs 

 to the RhodocriMidae. We refrain from proposing new generic names 

 for these straggling forms, as we cannot altogether depend upon the figures, 

 and we hope they will be taken up by investigators more familiar with 

 these types, and who have access to the specimens. 



3. PATELLIOGIIINUS Angelin. 



1878. Angelin. Iconogr. Criu. Suec, p. 1. 



1879. Zittel. Handb. der Palaeont, p. 368. 



Several of these species referred by Angelin to this genus 

 belong, in our opinion, to very distinct genera. His Pat. duplica- 

 tus has not only four arms to the ray, but as we judge from the 

 shape and size of the basals, evidentlj' had underbasals ; also the 

 first anal plate is in line with the first radials, while in all other 

 species of PatelliocyHnus those plates are ranged with the second 

 radials. In Pat. fulminatus the calyx is but imperfectly pre- 

 served, but we judge from what is exposed, that this species was 

 closely allied to another figured in Iconogr., PI. 18, fig. 16, as Melocr. 

 Volhorth.i.^ Both species have branching arms, unlike Patel- 

 lioci'inus, and are probably generically identical. We should 

 propose for them a new genus, if we had more perfect figures for 

 description. 



Zittel made Patelliocrinus a synon3'm of Dimerocrinus Phill., 

 wliich, however, has five basals instead of three, and underbasals. 

 In his classification he arranges Dimerocrinus with Dolatocrinus, 

 Cytocriniis with 3Iacrostylocrinus, and all under the Patellio- 

 crinidae. 



Patelliocrinus is one of those genera in which the arms as a 

 rule are neither single- nor double-jointed, and sometimes scarcely 

 interlocking at all, resembling herein Eupachycrinus and Eriso- 

 crinus of the Cyathocrinidse. 



Generic Diagnosis — General form oblong. Calyx patellifonn ; 

 symmetrj^ almost perfectly equilateral. 



' We take it that Melocr. Yolhortld is represented by PI. 7, figs. 7 to 11, 

 which is an entirely different thing from PI. 18, fig. 16. 



