288 Dr. P. H. Carpenter on the 



to find that Mr. Hambach lias so closely followed our classi- 

 fication of the various types hitherto referred to Pentremites. 



He further admits that the perforation of the deltoid pieces 

 may render it desirable to separate Granatocrinus from Pen- 

 tremites * : — " But then the name Granatocrinus ought not 

 to be chosen, as has been done by some of our American 

 writers and now repeated by Mr. Carpenter, as it will con- 

 fuse matters rather than make them more clear. The type 

 specimen for which Dr. Troost proposed the generic name 

 Granatocrinus, is Granatocrinus cidariformis, Troost = Pen- 

 tremites granulatus, Romer. But this species differs very 

 materially from P. Norwoodii, Owen and Shumard, as it 

 possesses no perforated deltoid pieces (the chief characters 

 for this genus, according to Mr. Carpenter), besides other 

 peculiarities in the arnbulaeral field." 



It has been already explained by Mr. Etheridge and 

 myself f that neither Granatocrinus nor G. cidariformis was 

 ever described by Troost, so that they have no zoological 

 value except as MS. names, while Pentremites granulatus was 

 only described by Romer from an internal cast \. Under 

 these circumstances we were obliged to seek for another 

 species which should serve as a type of the genus, and we 

 believed that " this may be most readily found in Pentremites 

 Norwoodi, Owen and Shumard, not only from its general 

 acceptance as a typical Granatocrinus, but as one of the 

 species first referred to this genus." With all due deference 

 to Mr. Hambach's dictum "as that of an authority on the 

 rules of zoological nomenclature, I believe that in following 

 the principles adopted by Hall §, Meek and Worthen ||, and 

 Wachsmuth and Springer ^f, we were taking a course which 

 was far less likely to lead to confusion than the estab- 

 lishment of a new generic type for Pentremites Norwoodi and 

 its allied species, which have been referred to the genus 

 Granatocrinus since the year 1862. 



After practically admitting the generic value of the type 

 represented by Pentremites Norwoodi as distinguished from 

 that of the ordinary P. Godoni **, Mr. Hambach states that 



* Trans. St. Louis Acad. vol. iv. p. 545. 



t Ann. & Mag. Nat. Hist. ser. 5, vol. ix. 1882, p. 237. 



% Op. cit. p. 44, Taf. iii. fig. 13. 



§ " Contributions to Palaeontology," loth Aun. Report New York 

 State Cabinet of Natural History, 1861-62, p. 318. 



|| ' Paleontology of Illinois,' vol. v. pp. 473, 509. 



If ' Revision of the Palteocrinoidea,' part i. p. 8. 



** This is the Pentremites Jlorealis of Say, a later name than that pro- 

 posed by De France ; but in spite of this fact Hambach persists in usiDg 

 Sav's name, which is transformed on p. 544 into P.forcalis. 



