EEPORT ON THE CRINOIDEA. 295 



that the character on which von Meyer established CJielocrinus is one of no systematic 

 value whatever. One of the two species on which he founded the genus was the 

 Encriniis pentactinus of Bronn.^ This name was proposed for a single specimen which 

 presented a very remarkable combination of characters. The cup appears to be that of a 

 tjqDical Encrinus with some twenty biserial arms. The stem has a rounded pentagonal 

 outline, and consists of about twenty -five joints, some of which bear verticils of five 

 cirri. Beyrich appears to consider these characters as of altogether subordinate value, 

 for he says^ — "die otwas abweichende Form des fiinfseitigen Stengels mit deutlich 

 eingesenkten Seiten kann eben so wenig fiir ein uuterscheidendes Ai'tnierkmal gelten, wie 

 die von Bronn beobachteten kurzen Cirren, welche anscheinend individuell hier und 

 da bei verschiedenen Encrinus-avten vorkommen konnen." There is a considerable 

 difference, however, between a regular verticillate arrangement of cirri and their occasional 

 presence here and there upon the stem, about which Beyrich does not speak very 

 confidently, so far as Enarinus is concerned. I cannot make out, indeed, that any stem 

 of an Encrinus has ever been described as bearing isolated cirri in the manner referred 

 to by Beyrich ; while, on the other hand, the verticillate arrangement has been discovered 

 by Picard * in an imperfectly preserved fragment from the Muschelkalk which he has 

 described as Encrinus beyriclii—" Dev Stengel ist von seinem untersten Theile an mit 

 Ranken versehen. Dieselben treten von unten herauf CTst sparlicher und in grosseren 

 Abstanden auf; am oberen Tlieile ist je das achte Sauleuglied ein Cirrentrager und 

 erscheint horizontal etwas verdickt. Die Anhaftestelle fiir die Cirre befindet sich 

 regelmassig auf der concaven Fliiche zwischen je zwei der fiinf Kanten, so dass ein 

 Wirtel von 5 Cirren den Stiel umgiebt." He continues — "Als Pentac.rinus wage ich 

 meinen Fund nicht auszusprechen. Denn obwohl die Fiille an Cirren und der ganze 

 Habitus der Saule sehr zu dieser Auffassung drangt, hat mich doch die Zusammensetzung 

 der Krone, soweit sie klar ist, bestimmt, bei der Gattung Encrinus zu bleiben." There 

 would seem therefore to be no doubt as to the occurrence of cirrus-verticils on the stems 

 of other Neocrinoids besides the Pentacrinidse ; while there are certain Palaeocrinoids 

 both in this country and in America which present the same character. Although, 

 however, this fact diminishes the value of that peculiarity of the Pentacrinidse which is 

 most evident at first sight, it does not follow that the verticillate arrangement of the 

 cirri in these other types is also associated with the presence of syzjj'gies at the nodes and 

 the mode of union of the internodal joints, which are such especial features of all the 

 Pentacriuidge. The Pentacrinus duhius of Goldfuss and Quenstedt shows these points 

 very well, the five petals being visible on the faces of many joints found in the Muschel- 

 kalk at different localities ; while the stem of von Schlotheim's specimen (6 inches long) 



' Ueber die Krinoideen-Reste im Muschelkalk, Neties Jahrh.f. Mineralogie, Jalirg. 1837, p. 32, Taf. ii. 



- Crinoideen des Muschelkalks, loc. cit., p. 36.' 



3 Zeitschr. d. deutsch. geol. Gesellsch., Jalirg. 1883, p. 201. 



