298 On Young Specimens o/ Anthenea sp. 



having three ; in some they have become fused together and 

 elongated. The tubercles themselves are not granulated, but 

 are developed from the granules, and on some of the plates 

 the process may be seen in various stages of development. 

 At the interbrachial arc the plates are wedge-shaped, 3 mm. 

 broad and 4 mm. long, but distally they become broader and 

 square. The terminal plate is small, being about the size o£ 

 the last paired marginal. Further, it is granulated and may 

 have tubercles. 



The infero-marginal plates approximate to the supero- 

 marginals, but continue on to the actinal surface also, and 

 are well-defined ; the change in shape distally is well illus- 

 trated in both specimens. The granulations are more regular 

 than on the upper series. On the second plate, counting 

 from the interbrachial arc, tubercles begin to develop and 

 increase in size and number toward the distal end of the arm ; 

 but they are not nearly so prominent as those on the super- 

 marginal plates. There are no pedicellarise on the marginal 

 plates. 



The madreporite, which occupies an interradial position, 

 measures 2 mm. ; it is lozenge-shaped and coarsely striated ; 

 the strise radiate centrifugally, very little convolution being- 

 noticeable. It is surrounded by a ring of evenly placed 

 granules. 



The specimens are undoubtedly young examples, and 

 correspond in some respects to the description of Anthenea sp. 

 described by Simpson and Brown (i), and also have certain 

 affinities with Siraster tuberculatus described b} r Clark (2). 

 But the differences are so marked that it is not possible to 

 accept Clark's very full generic and specific diagnosis as 

 applicable to the present specimens. Kcehler (3) gives a 

 very short account and a figure of Anthenea sp., juv. ; but he 

 does not refer to the ambulacral region, the description of 

 which is essential to a correct identification of the specimens. 

 The absence of tubercles from the centro-radial plates and 

 from the supero-marginals are points wherein Kcehler/ s 

 specimens differ from those above described. 



Literature. 



(1) Simpson, J. J., and Brown, II. N. Pudmose. 190O. " Asteroidea 



of Portuguese East Africa." Proc. Ii. Pays. Soc. Edinburgh, 

 xviii. (191 0-191 2) p. 50. 



(2) Clark, H. L. 1915. "The Echinodenns of Ceylon, other than 



Holothurians." Spolia Zeylanica, x. pt. 37 (1915), p. 86. 



(3) Kcehler, R. 1910. " An Account of the Shallow-water Aste- 



roidea." Echinoderma of the Indian Ocean, pt. vi. p. 91, pi. xvi. 

 fi*. 1. 



