DEEP SEA FAUNA 1319 



joints. The stem of Bathycrinus gracilis is long and 

 delicate ; in one example of a stem alone, which came 

 up in the same haul with the one nearly perfect 

 specimen which was procured, it was 90 mm. in 

 length. 



The general distribution of the deep-sea Asteridea 

 has already been referred to. Perhaps the most 

 obvious peculiarity which they present is the great 

 preponderance of the genera Astrogonium, Archas- 

 ter, Astropecten, and their allies. Genera belong- 

 ing to other groups do not apparently become less 

 numerous, for species of Asteracanthion, Cribrella, 

 Asteriscus, ,and Ophidiaster are as abundant as they 

 are at lesser depths ; but as we go down new species 

 with tessellated mailing on the disk and massive 

 marginal plates seem to be perpetually added. 



Of the twenty-six Echinoderms dredged from the 

 Porcupine, seven Porocidaris purpurata, Phor- 

 mosoma placenta, Calveria hystrix, C. fenestrata, 

 Neolampas rostellatus, Pourtalesia Jeffreys!, and P. 

 phiale are forms which have been for the first 

 time brought to light during deep-sea dredging 

 operations, whether on this or on the other side of 

 the Atlantic. There seems little doubt that these 

 must be referred to the abyssal fauna, upon whose 

 confines we are now only beginning to encroach. 

 Three of the most remarkable generic forms Cal- 

 veria, Neolampas, and Pourtalesia have been found 

 by Alexander Agassiz among the results of the deep 

 dredging operations of Count Pourtales in the Strait 

 of Florida, showing a wide lateral distribution, while 

 even a deeper interest attaches to the fact that 



