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



same year, and examined at Lund the original of Asterias midtiradiata, Linn. This 

 he found to have a pinnule on the first and a syzygy in the second joint above the 

 distichal and palmar axillaries, i.e., there are two palmars, with the axillary a syzygy. 

 He gave a careful description of this form, 1 to which, after his visit to Paris he added 

 some details derived from his personal examination of some examples collected by Peron 

 and Lesueur and by Quoy and Gaimard. His final diagnosis was headed Oomatula 

 (Alecto) multiradiata, Nobis ; 2 though, as we have already seen, he had referred the 

 Retzian specimen to the type of his new genus Actinometra. Dujardin and Hupe 

 described it under the latter name, 3 entirely on the basis of Miiller's diagnosis of it ; 

 but they made no mention of the specimens obtained by Peron and Lesueur and by 

 Quoy and Gaimard, which resemble the Retzian individual in having syzygies in all the 

 axillaries. 



I have already separated off one of these forms as Actinometra peroni, 4 owing to 

 its palmar series consisting of three joints, instead of only two as in the Retzian type, 

 which has no post-palmars and not more than twenty -five cirrus-joints. One of Peron's 

 specimens presents the same characters as Asterias midtiradiata, and I have since met 

 with a considerable number of similar individuals. But the spirit-specimen brought 

 from the Moluccas by Quoy and Gaimard, which was referred by Midler and afterwards 

 by myself 5 to Actinometra midtiradiata, must, I think, be separated from this species 

 on account of its larger number of cirrus-joints, and more numerous arms, owing to the 

 presence of post-palmar series. 



Two examples of it were obtained by the Challenger at Banda, and wUl be 

 described immediately as Actinometra sentosa (PL LX VI. fig. 4). 



I have had some doubts as to the projmety of separating Actinometra coppingeri 

 from Actinometra midtiradiata, the chief difference between the two being the absence 

 of palmars in the former and their presence in the latter. The character seems to be a 

 fairly constant one, however, as the two forms have not hitherto been found associated 

 together in one locality. Actinometra coppingeri is known from East Australia, 

 Singapore, Amboina, Banda, the China Sea, and Samboangan ; while palmars occur in 

 three examples of Actinometra midtiradiata from Bohol, another Philippine locality, 

 in two from Japan, in one from Sumatra, and in one from Torres Strait. It is a 

 generally more robust form than Actinometra coppingeri, with the lower brachials 

 relatively shorter and more overlapping ; while the spines on the cirri are of a much 

 more definite character than in that species. The second syzygy also is much further 

 from the calyx than in Actinometra coppingeri, especially in the Philippine examples of 

 Actinometra midtiradiata and in the Retzian type, in which last it may not occur till 

 the thirty -ninth brachial. 



1 Archivf. Naturgesch., 1843, Jahrg. ix. Bel. i. p. 133. a Abhandl. d. k. Akad. d. Wiss. Berlin, 1847 [1849], p. 261. 

 3 Op. cit., p. 210. * Notes from the Leyden Museum, 1881, vol. iii. p. 214. 



5 Journ. Linn. Soc. Lond. (Zool.), 1882, vol. xvi. p. 523. 



