50 Mr. F. A. Batlier on Eocldaris and 



respectively to Eotiaris n. g., Permocidaris n. g., an 1 

 Archceocidaris sens, restr. The last of these was discusse 1 

 in my previous paper (Nov. 1907) ; to the other two we 

 shall recur. Here it need only be noted that the result of 

 Lambert's action, as of Qaenstedt's, was to leave in Eoci- 

 daris only two of the original species — E. Icevispina and 

 E. scrobiculata. 



I conclude, then, in opposition to Professors Jackson and 

 Clark, that we are bound by the actions of Quenstedt, Torn- 

 quist, and Lambert to regard Eocidaris as restricted, partly 

 by elimination, partly by definite statement, to the two 

 Devonian species of Sandberger *. To prevent further 

 confusion it is necessary to fix on one of these as genotype, 

 and, in making a choice, regard should be had to the fact 

 that in ('. Icwispina the radiole has been described as well 

 as the interambulacrals. Tlierefore I decide on that species, 

 and to avoid all other sources of confusion I indicate as its 

 type (lecto-holotype) the original of Sandberger's pi. xxxv. 

 fig. 2 rt, which figure corresponds most closely with Sand- 

 berger's own description (1855, p. 382). 



Whether this conclusion is fortunate or unfortunate we 

 need not stop to decide, since that can have no bearing on 

 its correctness. At any rate, as will appear in the sequel, 

 it disposes of the name Eocidaris more effectually than the 

 action of Professors Clark and Jackson; therefore they, at 

 least, should be satisfied. 



Eocidaris lmvispina AND E. scrobiculata. 



It would be of more interest to discuss the validity and 

 systematic position of Eocidaris as thus interpreted, and here 

 it is indeed unfortunate tliat tlie materials for a decision are 

 so scanty. A few remarks may, however, be ventured on 

 Sandberger's specimens, which were very kindly lent to me 

 in January, 1908, by the Natural History Museum of tiie 

 town of Wiesbaden. My thanks are due to Geheimer- 

 Sanitatsrath Dr. Arnold Pagenstecher and to Dr. E. Lampe 

 for leaving the specimens in my hands so long. 



The specimens, which come from the Middle Devonian 

 Stringocephalus Limestone of Villmar, are all much broken, 

 with surfaces weathered and decorticated, and with the natural 

 margins of the plates destroyed. 



Taking the first genotype, Eocidaris Icevispina, we turn 

 to the lecto-holotype, the original of Sandberger's fig. 2 a 



* G. & F. Sandberger, 1855. The expression " Sandberger " is used 

 throughout, to avoid cumbrous repetition. 



