84 



Dr. P. H. Carpenter on the 



remarkable since, on p. 172 of the ' Encriniden,' a work which 

 Walther quotes freely, Quenstedt says that the second radial 

 of Solanocrinus " stets mit dem dritten Radial, einen Doppel- 



Fi-. 1. 



Fio;. 2. 



Fig. 1. — Actinometra pancicirra. A. Dorsal view of the lower part of a 

 ray, showing the syzygies (s) in the radials, distichals, and brachials, 

 X 2: cd, centro-dorsal ; r', first i-adial ; ?•'■', ?'^, second and third 

 radials united by syzygy ; d^, d', first and second distichals united by 

 syzygy ; b,^ IP-, first and second brachials united by syzygy. B. Ven- 

 tral" aspect of the united second and third radials, X 4. 



Fig. 2. — A. ( 'opy of a portion of Walther's diagram of the arm-structure 

 in Solanocrinns costatus : ax, third or axillary radial ; s, syzygy. B. 

 Copy of Walther's diagram of the arm-structure in <S'. gracilis, var. : 

 s, an apparent line of syzygy. 



gelcnk (axillare) innig verwachsen blieb, ahnlich den Syzy- 

 gien der Armglieder." These syzygies oi Antedon Eschrichti 

 are represented on fig. 16 of the same plate (Tab. 96) as 

 the figures of Solanocrinus costatus. 



I have Quenstedt's authority therefore for saying that there 

 is a syzygy between the two outer radials of Solanocrinus 

 costatus *, and I strongly suspect from the appearance of his 

 fig. 26 a on Tab. 96 that the apparently simple first brachial 

 is also a syzygial joint, just as in those recent ten-armed 

 Comatulse which have the two outer radials united by ^yzjgy 

 {Actinometra Solaris^ &c.). 



But whether this be the case or not, the condition of one 

 of Walther's own specimens, as interpreted by himself, seems 



* Compare his Tab. UG. figs. 26, 28, 43. 



