122 BULLETIN 82, UNITED STATES NATIONAL MUSEUM. 



In the year 1886 Dr. Jules Barrels gave a preliminary account of his studies 

 on the young of Antedon mediterranea, his complete monograph on the subject 

 appearing two years later; P. H. Carpenter published three papers, all more or less 

 important from a morphological point of view, the most noteworthy being one on 

 the variations in the cirri of certain European comatulids ; Wachsmuth and Springer 

 completed section two of part three of their work; Dr. Arthur Dendy gave an excel- 

 lent detailed account of the regeneration of the visceral mass in Antedon, and a 

 description of a curious 12-armed specimen of A. lifida; and Perrier published the 

 first part of his elaborate monograph on the structure and development of the 

 same species and A. moroccana. 



Mr. H. Bury in the following year gave a short sketch of the results he had 

 attained in the study of the early stages of Antedon mediterranea, the most important 

 being the discovery of the infrabasals, which had hitherto been unknown in the 

 comatulids, confirming in a most remarkable way the prediction of Wachsmuth 

 and Springer, who had announced then- probable existence upon evidence deduced 

 from the fossil crinoids. Bury's completed memoir appeared in 1888, a few months 

 after that of Barrois. At the same time Wachsmuth and Springer published a 

 critical account of the apical plates in blastoids, crinoids and cystids, discussing 

 the views advanced by Etheridge and Carpenter in their monograph on the blastoids 

 (1886); Mr. M. M. Hartog proposed the theory that the madreporic system of the 

 echinoderms is in reality a left nephridium discharging a current outward by means 

 of cilia; Vogt and Yung suggested that the sacculi are in reality symbiotic algse; 

 and Carpenter continued his contributions on echinoderm morphology, including 

 some rather sharp criticisms of the work of Perrier and of Vogt and Yung. 



The year 1888 was especially notable in the history of the structure and develop- 

 ment of the comatulids, for it witnessed the completion of three important mono- 

 graphs, and the entry of a new worker into the field of echinoderm morphology 

 who was destined subsequently to play a leading part. Bury and Barrois each 

 completed their memoirs on the young stages of Antedon mediterranea; both entered 

 into much greater detail than had ever been attempted before, working along the 

 most modern lines, and then- results showed an agreement in most particulars which is 

 indicative of the careful and painstaking way in which the work was carried on by 

 each. Dr. Otto Hamann announced in a preliminary paper some of the results of 

 his studies on the morphology of the crinoids, in which he supported the views of 

 the two Carpenters and Marshall, but took exception to many of those of Vogt, 

 Perrier and Jikeli. Wachsmuth and Springer brought out their most important 

 discovery of the ventral structure of Taxocrinus, showing that the palaeozoic Flexi- 

 bilia had. an open mouth like the recent crinoids; this was followed later (1890), 

 as a logical sequence, by their paper on the perisomic plates of the crinoids, which 

 led to the conclusion that the Palseocrinoidea and Neocrinoidea, as natural divisions 

 of the crinoids, are untenable. 



Systematically the great event of the year was the completion by P. H. Carpen- 

 ter of the Challenger volume on the comatulids, this constituting a fairly complete 

 epitome of all the knowledge on the subject, except in regard to such points as 

 had been exhaustively treated in the monograph on the stalked crinoids, and 



