Notices of Memoirs — B. Stuertz — Pahwzoic Starfishes. 119 

 ZLTOTICIES OIE 1 HVHIEIMIOIIRS- 



I. BeITRAG ZUR KeNNTNISS Pal^OZOISCHER SeESTERNE. VoU 



B. Sturtz, in Bonn. Palaeontographica, Band xxxii. 1886. 

 Mit 7 Tafeln. 



A Contribution to the Knowledge of Paleozoic Starfishes. 

 By B. Stuertz, in Bonn. Palaaontographica, vol. xxxii. pp. 

 75-98, pi. viii.-xiv. 



PERD. ROEMER called attention 1 some years since to the echino- 

 dermal fauna occurring in the roofing slates of Bundenbach 

 near Birkenfeld in Oldenburg, which belong to the horizon of the 

 middle beds of the Rhenish Lower-Devonian. More particularly, 

 Starfishes, including in the term the Asteroidea and Ophiuroidea, are 

 abundant. The calcareous tests of these animals have been replaced 

 by iron pyrites, and they are firmly imbedded in the hard slate in 

 such a manner, that at the time when Roemer wrote, only the 

 general outline of the animals could be discerned ; but within the 

 last year or two means have been found by which the slaty matrix 

 can be entirely cleaned away, and the skeleton of the animal laid 

 bare, so that the arrangement of the plates of the test, both on the 

 ventral and dorsal surfaces, can be ascertained. The insight thus 

 gained of the skeletal structure of these Devonian Starfishes has 

 enabled Herr Stuertz to make a comparison between them and the 

 more recent fossil and existing members of the group, and amongst 

 other results of his work he has discovered true Ophiuroids, with a 

 structure corresponding with that of living forms, which have not 

 jDreviously been known from Palaeozoic strata. These were associated 

 with the simpler Palaeozoic Ophiuroids. There are also in these beds 

 a number of true Asterids, associated with Encrinasters ; and a re- 

 presentative of the existing genus Astropecten. 



The single species of the Ophiurece verce belongs to the genus 

 Ophiarella, Ag., and is named 0. primigevia, St. In the group of 

 the Protophiiirece are included Palaeozoic Ophiuroids which possess 

 corresponding ambulacral plates on the ventral side of the arms. 

 The author agrees with Liitken in regarding these as doubled ventral 

 shields, which cover the ambulacral system. In this group the 

 author places the Protaster Miltoni, Salter, and P. leptosoma, Salter, 

 and also a new genus, Furcaster, with a single species, F. pnlceo- 

 zoicus, St. 



Fresh observations have been made on the doubtful genus Heliaii- 

 thaster, Roemer, examples of which also occur in Devonshire as well 

 as at Bundenbach, but they are still insufficient to determine its true 

 position. The author regards it as an Ophiuroid Starfish with from 

 14-16 arms and a tolerably large disc. 



The author gives the name Ophio-Encrinasteria? to a group of 

 forms which stand in near relationship to Ophiuroids, but possess 

 peculiarities of structure which ally them to the Encrinasteridae. In 



1 Palaeontographica, Band ix. 1862. 



