REPORT ON THE ASTEROEDEA. 323 



unquestionably characteristic examples of the form named Stellaster incei by Gray ; whilst 

 smaller examples from the same locality would, if studied independently, be referred with 

 little hesitation to his Stellaster belcheri. The specimens from the other localities are 

 small, and have all the characters of young Stellaster belcheri. 



The number of tubercle-bearing plates varies considerably, and their position is by no 

 means constant. Some examples of Stellaster incei have the disk much more convex and 

 elevated than others ; the tumidity is consequently not a reliable character. I am unable 

 to point out any real specific difference between Stellaster incei and Stellaster belcheri, 

 and I am constrained to believe that they are growth stages of the same form. I have 

 acted on this impression in my determination of the Challenger material, and I have pre- 

 served the name of the adult form. If my assumption is correct, the name Stellaster 

 belcheri should be ranked as a synonym. 



The young form (Stellaster belcheri) has been ably described and figured by Ltitken ; l 

 and I would only remark that the apertures of the papulae pores in the young of this form 

 are guarded by a rim of squamules or granules as noted by Liitken, who states that they 

 are "omgivue af en lille Kornkreds hver." This structure has been regarded by Studer 2 

 as a special characteristic of his Stellaster squamulosus, which also appears to me to be an 

 immature form. 



2. Stellaster princeps, n. sp. (PI. LVIII. figs. 1-2). 



Eays five. R = 137 mm., r = 40 mm. R < 3"5 r. Breadth of a ray near the base, 

 between the third and fourth marginal plates, 30 mm. 



Eays comparatively elongate, broad at the base, and tapering gradually throughout up 

 to the extremity. Disk large. Interbrachial arcs widely rounded. Abactinal area regu- 

 larly convex over the disk. Actinal area subplane. 



The abactinal area is covered with polygonal plates which on the radial regions of the 

 disk and the inner half of the rays are more or less incised for the papular groups, and thus 

 assume a strikingly stellate form. About seven longitudinal series of plates may be counted 

 at the base of the ray, about three midway along the ray, but at the tip only the median 

 series is represented and its continuity is broken by the union of the marginal plates. 

 The plates in the interradial areas are very large, especially a group of four external to the 

 primary basal plate. All the plates are covered with a fine granulation imbedded in a 

 continuous membrane. The third or fourth radial plate, counting from the centre of the 

 disk, bears a short, robust, conical, sharply pointed tubercle, which is more or less spiniform. 

 Five or six plates further outward, near the base of the ray, is a similar but slightly 

 smaller tubercle, or there may be as many as three to five at irregular distances apart. 



. 1 Videnskab. Medd. naturh. Foren. i KjQbcrihavn, 1871, p. 247, pi. v. fig. 3. 



2 Anhang z. d. Abhandl. d. k. preuss. Akad. d. Wiss. Berlin, voiu Jahre 1884, p. 33, Taf. iv. figs. 6o-6c. 



