442 BULLETIN 82, UNITED STATES NATIONAL MUSEUM 



In 1911 in discussing the type specimen of Miiller's Alecto novae-guineae, which 

 I had recently examined in the Leyden Museum, I remarked that "it almost entirely 

 lacks the rough and spinous character presented by the Philippine specimens recorded 

 by myself as novae-guineae." These last were the specimens mentioned above. 



Early in 1910 I wrote a report on the third consignment of crinoids sent by 

 the Albatross from the Philippines. Among these were 4 specimens (from station 

 5356) which I recognized as representing a new form, which I described in a paper 

 published early in 1911 as Comaster fruticosus. No comparison was made at the 

 time between these specimens and others previously received from the Philippines. 



On my return from Europe in the autumn of 1910 I discovered that the Albatross 

 specimens from the Philippines were quite different from Miiller's type, and in the 

 manuscript of my monograph on the crinoids of the Indian Ocean which I was then 

 just completing I wrote that there is a strong possibility that novae-guineae may 

 turn out to be synonymous with typica, since the type of novae-guineae at Leyden 

 when compared with the specimen of typica in the same museum described by 

 Carpenter is found to differ only in the lesser number of the arms and in its thinly 

 discoidal centrodorsal on which are cirrus sockets. I continued that in this "case 

 the Philippine form would require a new name; it might be appropriately called 

 philippinensis." These remarks were published in 1912. 



In the original description of Comaster sibogae, published in 1912, I compared 

 this species with it, and in 1918 I recorded a large and a small specimen in the Siboga 

 collection. 



COMASTER SIBOGAE A. H. Clark 



Plate 51, Figure 152 



Comaster sibogae A. H. CLARK, Proc. Biol. Soe. Washington, vol. 25, 1912, p. 21 (description; 

 Siboga station 318); Unstalked Crinoids of the Siboga Exped., 1918, p. VIII (discovery by 

 the Siboga and its significance); p. 36 (in key; range); p. 40 (detailed description; station 

 318); p. 276 (listed); pi. 14, fig. 17. 



Diagnostic features. Very similar to fruticosus from which it differs in having 

 the cirri longer and more slender, more than one-tenth of the arm length, with the 

 longest segment from three to three and one-half times as long as the median width. 

 The dorsal spines are more prominent than in fruticosus. 



Description. The cirri are XXII, 13, 13 mm. long. The first segment is short, 

 the second is twice as long as the median width, the third is about three times as 

 long as the median width, and the fourth and fifth are the longest, from three to 

 three and one-half times as long as the median width. The following segments de- 

 crease rapidly in length so that the antepenultimate is slightly longer than broad, and 

 the penultimate about as long as broad. The fifth is a transition segment. The 

 segments following have small, but sharp and prominent, dorsal spines which are 

 acutely triangular in end view. The opposing spine is subterminal, slender, and very 

 sharp, in height equal to about one-third the lateral width of the penultimate seg- 

 ment. The terminal claw is nearly or quite twice as long as the penultimate seg- 

 ment, and is very slender and moderately curved basally, becoming nearly straight 

 in the outer two-thirds. 



