JAPANESE ASTEROIDEA. 143 



opinion, be regarded as of specific importance. As to the radial 

 ratio, it varies in Japanese specimens from 2.7-4.8. Calculating 

 from the dimensions given by de Loeiol, it is very nearly 5 for 

 the Mauritius specimens ; but Müller and Teoschel give it as 

 4.3. It is also to be remarked that in Mauritius this starfish 

 appears to grow to a larger size than in Japan ; for the specimen 

 which is figured by de Loriol and referred to as of " petite 

 taille," would rank among the larger ones of my specimens. 

 With this more luxuriant growth the radial ratio would be in- 

 creased and the spines also would be larger, especially the lateral 

 ones of the inferomarginals ; and the apparent difierence between 

 the descriptions of Müller and Troschel on the one hand and 

 DE LoRioL on the other as to the armature of the inferomarginals 

 may also be explained. As to the single specimen referred to by 

 de Loriol as Atropeden sp., it need hardly be remarked that the 

 only point of importance to be considered is the continuous 

 character of the superomarginal spines, which has been shown 

 to occur also among Japanese specimens of Astropecten scoparius. 

 I think therefore that I am justified in concluding that Astropecten 

 hempricliii and Astropecten scoparius are one and the same species. 



Astropecten polyacanthus Müller & Teoschel. 



(PI. m, figs. 42-51.) 



Next to Astropecten scoparms this is probably the commonest species of 

 tlie genus in Japan. It is placed by Müller and Troschel in theh* second 

 group, in "which also come the two synonyms mentioned below. According 

 to DE Loriol ['85, p. 76] this species was illustrated for the first time by 

 Sa-sœgny ['03, pi. iv, fig. 1], but its first description was xrablished in the 

 " System der Ästenden " as foUows [Müller u. Troschel, '42, p. 69, 2 figs.] : 



