PART 5 A MONOGRAPH OF THE EXISTING CRINOIDS 405 



his results with those of the other. Had either commented on the differences in the 

 articular faces of the radials between Antedon bifida and Heliometra glacialis, attention 

 would at once have been directed toward this line of investigation, so important in 

 connection with fossil species, which was entirely neglected until P. H. Carpenter 

 took it up in connection with his work on the Challenger collections many years later. 



Though this species had been first found as early as 1773, first recorded in 1774, 

 and described in detail in 1841, the first figure of it was published by Quenstedt in 

 1876 in connection with his monograph on the fossils of Germany. 



Following the publication of the memoirs of Sir Wyville Thomson (1865) and 

 Dr. W. B. Carpenter (1866), very considerable interest had been aroused in the struc- 

 ture and anatomy of these curious animals. This led to the publication by Greeff, 

 Lange, and Ludwig in 1876 of the results of independent investigations based chiefly 

 upon Antedon mediterranea, but in all three cases, with additional information derived 

 from the study of H. glacialis, an especially attractive species with which to work on ac- 

 count of its large size. In the same year both W. B. and P. H. Carpenter discussed 

 certain of the points brought out in these papers. 



In 1877 Ludwig published additional anatomical notes on the species, and P. H. 

 Carpenter presented a further discussion of certain anatomical features and described 

 the centrodorsal, following this in 1878 with a description of the basal rays and the 

 rosette. In this year Dr. Anton Stuxberg gave a preliminary account of the material 

 in the collections made by the Vega, and Sir George Nares published a short popular 

 notice of their occurrence in Franklin Pierce Bay as he met with them while on the 

 Discovery; he remarks that these beautiful crinoids, closing and opening their pinnules 

 when exposed to the atmosphere, reminded him of sensitive plants. 



In 1879 P. H. Carpenter noted the occurrence of this species in the Challenger 

 collections, and hi another paper discussed its structure and anatomy at con- 

 siderable length. In the same year Ludwig republished in collected form all his ob- 

 servations regarding it, van Lidth de Jeude noted its occurrence in the Willem Barents 

 collection of 1879, and Prof. Addison E. Verrill listed it (with the varietal name acadiae) 

 among the invertebrates of New England. 



In 1880 Stuxberg described what he called the Antedon- Astrophyton association 

 (see pp. 391-392), which he had studied hi the Siberian Polar sea off Taimyr Land, 

 d'Urban recorded this species from one of the Willem Barents stations of 1S79, and P. H. 

 Carpenter published further notes on its structure and anatomy, studying especially the 

 radial articular faces of the radials in connection with fossil forms. 



The best popular account of this species which has yet appeared, accompanied by 

 an excellent and characteristic figure, was published by Nordenskiold in his narrative 

 (hi English) of the voyage of the Vega in 1881. In the same year Duncan and Sladen 

 described its occurrence hi the northwest Greenland area as it was found by the Alert 

 and Discovery. Additional notes on the nomenclature, structure, and anatomy were 

 published by P. H. Carpenter, who also recorded it from Davis Strait hi 410 fathoms 

 (749 meters) and from Challenger Station 48, south of Halifax, in 51 fathoms (93 

 meters). 



Prof. Verrill in 1882 in two papers recorded this species from a number of local- 

 ities on the fishing banks off Nova Scotia, remarking that it is especially common off 

 Cape Sable. At the same tune Hoffmann listed it from several of the Willem Barents 

 stations occupied in 1878 and 1879, and Stuxberg gave a detailed account of the Vega 



