28o DISCOVERY REPORTS 



NOTE: All line figures are five-sixths the stated enlargement on account of necessary reduction of 

 original plates. 



Fig. A 



1. Perknaster fuscus, cotype. Spinelets of abactinal paxillae from ray, 0-54 and 0-55 mm., x 100. la. 

 Abactinal spinelet, base of ray, 0-55 mm., x 100. ib. Actinal intermediate spinelet, 0-65 mm., x 100. 

 ic. Inferomarginal spinelet, 0-54 mm., x 100. id. Abactinal spinelet from near end of ray, 0-45 mm., x 100. 



2. Perknaster fuscus, cotype. Profile of abactinal paxillae, pedicel 0-22 mm. high, x 50. 2 a. Larger abactinal 

 plate, x 50. 2b. Small paxilla pedicel o- 18 mm. high, x 50. 2c. Side view of abactinal plate with pedicel, 

 0-22 mm. high, x 50. 2d-2f. Three adambulacral spines from near proximal end of furrow, 1-7, 1-4 and 

 0-85 mm. respectively, x 40. 2g. Tip of 2/, x 100. 



3. 3 a. Perknaster densus. Two abactinal plates, base of ray, seen from side, pedicel 0-45 mm. high, x 50. 

 36. Two abactinal spinelets proximal third of ray (from plates 3, 3 a), 0-48 and 0-45 mm. long, x 100. 3 c. 

 Spine from actinal interradial area, 0-58 mm. long, x 100. 3^. Adambulacral plate, mouth toward right, and 

 furrow spines on lower side of figure shown extended over furrow, x 15. T,e. Four of 8 adambulacral spines 

 of seventh plate, the longer spine from each of the 4 longiseries, x 30: a, aboral furrow spines, 2 mm.; 

 b, adoral of second row, 1-5 ; c, adoral of third row, 0-93 mm. ; d, adoral of outer row, o-S mm. 3/. Adambulacral 

 armature of a seventh plate seen from oral side, the spines erect and closely apposed as is usual in this 

 specimen. 



4. Perknaster fuscus, cotype. Fourth to sixth adambulacral plates; lowest plate the fourth, x 20. 



