30 



a few of them bear a central spine each that is surrounded with 



tubercles. There are no pores or passages that penetrate the 



vault between the arms. 



This species is distinguished by its wide calyx, low vault, pecu- 

 liar form, surface ornamentation and number of arms. 



Found in the Hamilton Group, at Louisville, Ky., by G. K. 

 Greene, in whose honor the specific name is proposed, and now 

 in the collection of S. A. Miller. 



Remarks. — We have described and illustrated fourteen species 

 of Dolaiocrinus, being all that are now known from Ohio, Indi- 

 ana and Kentucky. Eleven of these are new to science, one of the 

 others has never before been figured, and the other two are illus- 

 trated and redescribed for the purpose of showing characters not 

 heretofore known. We call attention to the fact that no one has 

 discovered an azygous opening in any of the species, and this im- 

 portant character or part of the ordinary structure of crinoids may 

 fairly be said not to exist in this genus. D. magnificus and D. 

 aureafus have each an azygous side to the calyx and vault and 

 D. greenei has two azygous areas in the calyx, while none of the 

 other species have an azygous side or azygous area. 



D. grandis, D. Incus, D. marshi, D. stellifer and D. approxi- 

 mahis have orifices entering the body through the vault, between 

 the arms, an important structure having no existence in D. magnif- 

 ies, D. ornatus, D. ornatus var. asperatus, D. bulbaceus, D. 

 vennslus, D. aureaias, D. lineolatus or D. greenei, and whether 

 or not the character belongs to D. spinosus is not determined. 

 These orifices, though conspicuous in the species to which they 

 belong, have not, so far as we are advised, been heretofore men- 

 tioned, and it would seem, therefore, appropriate for us to state 

 more fully the structure and appearance and the possible or proba- 

 ble physiological functions with which they were connected. 



We regard them as excurrent orifices for the reason that they 

 cross the plates of the calyx at the summit by a furrow and en- 

 ter the vault horizontally, which is inconsistent with any other 

 hypothesis. What flowed through the orifices flowed through the 

 channels across the thickness of the plates of the calyx, for we 

 cannot conceive of any other utility or purpose of the furrows. 

 Nothing could have flowed through the furrows and entered the 

 orifices for the purpose of gaining access to the interior of the 

 body, for there was no means of propelling anything in that direc- 

 tion. Endosmosis would not take place in that way. 



