1885.] Natural sciences of Philadelphia. 257 



all recognize as interradials ; the inner ones, however, were desig- 

 nated by Roemer as " kleine interradiale Stiicke, welclie von dem 

 Mittelpunkte der Scheitelrlache zu den Armeu verlaufen." 

 Schultze called them " Scheitelstiicke," Zittel and De Loriol 

 " orals," and all speak of open ambulacral furrows leading to the 

 arms, and of an external mouth. The latter two writers refer the 

 genus to the Haplocrinidse, Schultze to the Platycrinidae. Car- 

 penter (Chall. Rep., p. 103), regards Goccocrinus, " like the recent 

 Holopus, to be permanently in the condition of a Crinoid larva in 

 which the orals have not yet moved away from the raclials, 

 though separated from one another." In the interpretation of 

 the plates he agrees with Zittel, De Loriol and Allman. 



A similar interpretation was given by us in our generic descrip- 

 tion in Part II, when we took the plates of the inner ring to be 

 identical with the so-called " orals " of Gyathocrinus, but this has 

 been abandoned after finding the latter plates to be interradials, 

 and the}' are now regarded by us as secondary interradial plates. 

 When we adopted Zittel's interpretation, we were misled by the 

 superficial resemblance to the oral pieces in the recent genus 

 Hyocrinus, overlooking the fact that the latter rest within a belt 

 of perisomic pieces, in place of interradials in the former. Gocco- 

 crinus bacca, as seen by Roemer 's figure (Fauna West. Tenn., PI. 

 4, fig. 5 c), has three interradials arranged transversely as in the 

 Platycrinidae, the outer ones resting against the secondary 

 radials. The presence of higher interradials in this species is 

 sufficient to prove satisfactorily that the genus Goccocrinus is no 

 Haplocrinite, and that it does not even go with the Inadunata. 

 It is possible that Goccocrinus rosaceus had exceptionally but 

 one interradial within the first row, but as a member of the 

 Camarata it must have possessed higher interradials, like other 

 Palaeocrinoids in which the interradials come in contact with the 

 higher radials, contrary to the Inadunata, which have, as a rule, 

 a single interradial plate. 



We doubt if even Carpenter, although he is inclined to accept 

 the upper series of interradials in Platycrinus as anambulacral 

 plates, will go so far after examining our diagrams, as to include 

 among these the lateral plates of the proximal row, either in 

 Platycrinus or Goccocrinus, which he overlooked in both genera. 

 Goccocrinus is certainly not in the same morphological condition 

 as Holopus, even admitting, which we do not, that the upper 



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