REPORT ON THE ASTEROIDEA. 253 



and sometimes a second pair stand immediately below these, in the place of the first 

 actinal or superficial spines. The marginal spines and actinal spines are subequal to 

 one another in size, and diminish as they recede from the mouth ; the actinal spines 

 forming a series parallel to the median suture of the mouth-plates. 



The actinal interradial areas are very small, and do not contain more than two or 

 four small intermediate plates, which bear either a forficiform pedicellaria or a group of 

 small ciliary spinelets. 



The madreporiform body is hidden by paxillse. 



Colour in alcohol, varying between light yellowish drab and dirty greenish grey ; 

 with a very dark broad band, almost black in some specimens, dark sage green in others, 

 along the median radial line, extending to the centre of the disk, in some specimens fading 

 out gradually at the sides, in others terminating more abruptly. At the extreme tip of 

 the ray the whole area is of this dark colour, whilst the ocular or terminal plate is white, 

 and hence very conspicuous. 



Locality. — Yokohama. May 6, 1875. Depth 5 to 25 fathoms. 



Remarks. — This species is perhaps most nearly related to a Luidia from Singapore, 

 preserved in the University Museum at Copenhagen, which bears the manuscript name of 

 Luidia chefuensis, Grube ; but the two forms are distinguished by a number of well- 

 defined characters. In Luidia limbata the paxillae are larger and more definitely square, 

 and the lateral spine is of a different shape. The armature of the adambulacral plates is 

 different, wanting altogether the comb of four or more spinelets running parallel to the 

 furrow, which in Luidia chefuensis succeeds the two single curved spinelets. In like 

 manner there is no trace of the second comb, parallel to the furrow, of four to six ciliary 

 spines, probably situated on the intermediate plate between the infero-marginal and 

 adambulacral plates. 



I should here state that I have not been able to find any published description of the 

 species now mentioned under the name of Luidia chefuensis. 



In the University collection at Breslau there is another Luidia, which bears the 

 manuscript name of Luidia singaporensis, Grube, but which seems to me to be the same 

 as von Martens' Luidia maculata, var. quinaria, and different from Luidia chefuensis. 



I am inclined to think that the so-called variety quinaria of Dr von Martens is really 

 a species distinct from Luidia mactdata. 



4. Luidia clathrata (Say), Liitken. 



Asterias clathrata, Say, 1825, Journ. Acad. Nat. Sci. Philadelphia, vol. v. p. 142. 



Luidia clathrata, Liitken, I860, Videnskab. Medd. naturh. Foren. i Kj0benhavn for 1859, p. 37. 



Locality.— Challenger Expedition : Bahia. Depth 7 to 20 fathoms. 

 Other Localities. — North Carolina, South Carolina, Florida, Martinique, Hayti, St 

 Thomas, Rio Janeiro. 



