28 THE VOYAGE OF H.M.S. CHALLENGER. 



spines are cylindrical, generally densely set, and sometimes collected in tufts, as in 

 Antipathes humilis. They are frequently unequal on the two sides of the pinnule, being 

 longer on the side occupied by the polyp. In the second type the spines are triangular 

 and compressed. In this case the spines are disposed regularly in quincuncial order 

 around the pinnules, ' generally, though not always, disposed spirally, and showing no 

 tendency to elongation in the neighbourhood of the polyps. According to Pourtales' 

 experience those species having triangular spines have polyps with longer tentacles than 

 those in which the spines are cylindrical, and the polyps are usually more regular in 

 shape. " In a very few instances the tentacles are found retracted, as figured by Lacaze 

 Duthiers ; in most cases they are simply contracted, and in many species they are 

 probably not retractile at all." Pourtales was also of opinion that the shape, size, and 

 arrangement of the spines probably afford reliable specific characters. He is indeed the 

 first author who has given us reliable information on these points in the description of 

 new species. Unfortunately Pourtales was not spared to complete the much needed 

 revision which he contemplated, but the foregoing account of his views on the subject 

 will show that the lines on which he proposed to work are, in the main, those which have 

 been adopted in the present monograph. 



Gray in 1868 (49) described a new species of Cirrhipathes (C. Jiliformis) from 

 Australia, but as in other species described by this author, the polyps were not 

 observed, and the description is insufficient for specific purposes. The type is in the 

 collection of the British Museum, as well as three or four other specimens of the same 

 species collected more recently. 



Duchassaing (54), in his final review of the Zoophytes and Sponges of the Antilles, 

 describes shortly four new species. Two of these, Arachnojxtihes columnaris and 

 Rhipidipathes tristis, have since been observed by Pourtales, who has figured a 

 specimen of the former, and also the arrangement of the spines in both species. The 

 other species described by Duchassaing, viz., Antipathes taxiformis and Antipathes 

 melancholica, are very imperfectly described ; the latter is probably allied to Antipathes 

 dissecta, Duchassaing and Michelotti. 



Liitken in 1871 (55) described a new form, Antipathes arctica, taken from the 

 stomach of a shark captured off the coast of North Greenland. This is the first and 

 only record (with the questionable exception of Antipathes boscii already referred 

 to) of the occurrence of any species of Antipatkidse north of the Mediterranean and 

 the southern States of North America. Liitken in a footnote mentions that Sir 

 Wyville Thomson had informed him that specimens referable to this group had been 

 collected during the expeditions for the exploration of the deep water around the 

 British Islands. I am, however, unable to find any reference to them in Sir Wyville 

 Thomson's published works, or in the zoological results of the various expeditions 

 referred to. 



