14 DE. P. H. CAKPENTEB, ON CERTAIN POINTS 



merous, with the two infrabasals of the aual side (CD) united 

 into one large plate. Echinoencrinus and Caryocrinus are taken 

 by Steinmann * as the types of his group Cystocrinoidea, while 

 Lepadocrimts, which he unites with Pseudocrinus, is placed with 

 GlyptosphcBva and JSchinosphcera among the Eucystoidea, in 

 which there are " keine deutlichen freieu Arme, dagegen meist 

 Ambulacralfurchen oder -felder entwickelt." Steinmann does 

 not state his views respecting Callocystis and Apiocystis ; but I 

 cannot see that their appendages, or tliose of Lepadocrimts and 

 Pseudocrinus, are in any way so markedly different from those of 

 Echinoencrinus as to justify a separation of this kind. The 

 ambulacra of Echinoencrinus are very short, and hardly extend 

 beyond the peristome, so that the appendages are limited to its 

 immediate neighbourhood, forming what Steinmann calls "freie 

 Arme an der Grrenze der Ober- uud TJnterseite." But Lepado- 

 cystis Moorei and Lepadocrinus Q-ehhardi, together with Apiocystis 

 and Callocystis, afford a complete transition to the condition of 

 Pseudocrinus ; and considering the resemblance in the composition 

 of their dorsal cups, I should include all these genera in the 

 Cystocrinoidea, leaving the more irregular forms with numerous 

 plates as the Eucystoidea. 



We have seen that one of the infrabasals in the pentamerous 

 EcJiinoencrinus-grou-p is a double plate (PI. I. figs. 3-8 ; 3), and 

 that there are two such plates in the hexamerous Caryocrinus 

 and its allies (PI. I. figs. 1, 2). This is also the case in the penta- 

 merous Hypocrinus and Gryptocrimis.- In both types, so far as 

 I can make out from the published figures of them, the single 

 infrabasal is that of the right anterior ray (B), those of radii AE 

 and CD being respectively fused (PI. I. fig. 9). 



Hypocrinus f is certainly a very singular form, and one would 

 like to know more about it. The tbree infrabasals are followed 

 by five equal and similar basals, and these again by five radials 

 which are described by Beyrich as bearing " die Ansatzstellen 

 der Arme." The aual opening is placed at the top of one of the 

 basals, also notching the lower angles of the two radials which 

 rest upon it, a condition which recalls that of Gasterocoma among 

 the Crinoids. Glyptocystis multipara presents a similar pecu- 

 liarity (PL I. fig. 8), and the same would be the case in Cystohlastus 



* Op. cit. p. 182. 



1" See Beyrich, " Ueber eine Koblenkalk-Fauna von Timor," Abhandl. d. k 

 Akad. d. Wise. Berlin, 1864, p. 83, Taf. ii. lig. 16. 



