A MONOGRAPH OF THE EXISTING CRINOIDS 435 



much elongated segments. He included tuberculata and spicata in a group character- 

 ized by postradial series with marginal projections and by having P 3 not greatly 

 shorter than P 2 ; indica, with winch tuberculata and spicata were contrasted, was said 

 to have the margins of the postradial series smooth and P 8 considerably shorter than 

 P 2 . Later in the text he said that indica differs from spicata and tuberculata in the 

 slighter development of marginal processes at the bases of the rays. The difference 

 between tuberculata and spicata was said to be that tuberculata has XL cirri and the 

 the IBr 2 (axillaries) more than twice as long as the IBr^ while in spicata there are 

 XXV cirri and the IBr 2 (axillaries) are less than half again as long as the IBr,. Car- 

 penter included marginata with clemens {=Heterometra quinduplicava) in a special 

 section of the Palmata group characterized by the possession of IIBr series, but no 

 further division, and therefore in the key did not compare it directly with spicata or 

 tuberculata. 



In 1889 Carpenter recorded and gave notes upon a single specimen from King 

 Island in the Mergui Archipelago and referred it to spicata. He again compared 

 spicata with tuberculata and indica and said that in the latter marginal projections 

 seem to be absent from the sides of the division series. In this case he seems to have 

 interpreted indica wholly on the basis of Smith's figure, as he did when preparing the 

 key to the species of the Palmata group in the Challenger report; but in other cases 

 his references to indica indicate that he considered as belonging to that species the 

 form herein described as Stephanometra protectus (see p. 443). 



In his key to the species of the Palmata group published in 1891 Dr. Clemens 

 Hartlaub placed spicata, tuberculata, and indica among the species characterized by 

 the possession of IIIBr and sometimes additional division series. The two first are 

 included in a section characterized by the possession of marginal processes on the 

 elements of the division series, while indica was said to have no marginal processes on 

 the division series, 30 arms, and P 2 with more than 12 segments. He grouped spicata 

 and tuberculata in a division characterized by having P 3 of the same character as P 2 

 and only slightly or not at all smaller, contrasting them with monacantha (=protectus) 

 in which P 3 is much shorter than P 2 and is not stiff and styliform ; sjricata he said has P 2 

 with 16-20 segments and the outer pinnules long and filiform, while in tuberculata P 2 

 has less than 16 — usually about 12 — very long segments. Hartlaub had examined 

 the type specimen of spicata at Leyden, and also a specimen that he identified as 

 tuberculata — evidently the one from Ruk, as that is the only one of the three in the 

 Hamburg Museum in which P 4 resembles the succeeding pinnules more than it does 

 P 3 — and compared the forms in considerable detail. 



In my first revision of the old genus Antedon published in 1907 spicata and 

 tuberculata were referred to the genus Himerometra, from which they were removed 

 to the new genus Stephanometra in 1909. Later in 1909 I recorded Stephanometra 

 marginata from Singapore, my records and notes being based upon a misidentified 

 specimen of this species. 



In 1911 I published a redescription of the type specimen of Antedon spicata, which 

 I had examined in the Leyden Museum the previous year, and in another paper I 

 recorded, as Stephanometra sp., a specimen from New Caledonia. 



