350 Dr. F. A. Bather — On Psalidocrinus remesi. 



over the muscle-fossa, so as almost to cover the ridge which separates 

 this fossa from that for the iiiterarticular ligament ; in B (Text-fig. 4) 

 the whole plate slopes more inwards, so that this ridge is clearly 

 exposed and the muscle-fossa itself is partly visible. 



It follows from the differences in the radial facets that there was 

 a corresponding difference in the arms. 



From the differences in the patinal cavity»and the relations of the 

 interradial processes, so far as they are preserved, one may also infer 

 that there was some difference in the portions of the interradial 

 processes not preserved in A. Whether this difference was so great 

 that the processes did not meet over the oral centre as they do in B 

 and in Apsidocrintfs, one cannot say. Dr. Remes believes that they 

 did so meet. In either case the large size of the interradial processes 

 in A indicates an approach to the apsidal or psalidal character, and so 

 far justifies Dr. Remes in his removal of the specimen from 

 Miffe7iiacrinus. 



Time and opportunity do not permit me at pi'esent to make a 

 thorough study of the numerous genera that have been established in 

 the Eugeniacrinidse since I last attacked the subject. Dr. Remes 

 believes that Psalidocrinus is a homoeomorph of Apsidocrinus, having 

 been modified from J^ugeniacrintis in the same way as Apsidocrinus 

 was modified from FhyUocrimis. But while it is fairly safe to 

 associate Apsidocrinus with Phyllocrinus, it is by no means clear that 

 Psalidocrinus is so intimately connected with Eugeniacrinus. The 

 Eugeniacrinidse, as restricted by Jaekel (1907), are distinguished inter 

 alia by the very small size of their interradial processes and the 

 correspondingly peculiar development of their primaxils, which can 

 meet centrally over the patinal cavity. This line of development is 

 the converse of that followed by the Phyllocrinidse (Jaekel, 1907), 

 in which the interradial processes are large and may meet centrally, 

 while the prinuixils are unspecialized. Therefore Psalidocrinus 

 cannot well be derived from a Eugeniacrinid in Jaekel's sense. On 

 the other hand, the large size of the radial facets justifies the 

 contention of Dr. Remes that Psalidocrinus is not a descendant of 

 Phyllocrinus. We must therefore seek for an ancestor among more 

 primitive Holopodidae, such as Sclerocrinus and Cyrtocrinus. 



Provisionally, at any rate, Psalidocrimis is to be accepted. But 

 the principles governing our acceptance themselves render it difficult 

 to place the genus in any one of the families as defined by Jaekel 

 (1907). Logically, one ought to erect a new family for it, but until 

 further evidence is forthcoming it is preferable to call it merely a 

 Eugeniacrinid sensu lata. 



It is, however, necessary to distinguish specimen B from specimen 

 A. The latter is the holotype of Eugeniacrinus stramhergensis, Remes. 

 Therefore I make B the holotype of a new species, Psalidocriiius 

 remesi ; and, in accordance with the express instructions of Dr. Remes, 

 that species is to be regarded as the genotype of Psalidocrinus. The 

 conclusions of this note are summarized in the following diagnoses : — 

 Psalidocrinus, Remes. 



A Eugeniacrinid with interradial processes stout and elevated so as 

 to coalesce centrally over the patinal cavity. Radial facets wide, 



