4. Paxillar spinules long, slender, movable; 



paxillae in irregular narrow transverse 



ro-ws Astropecten ameTicanus 



Paxillar spinules small, clavate, fixed; 

 paxillae in regular wide transverse 

 rows Astropecten. nuttingi 



5. All superomarginals without spines or 



tubercles A stropecten mtidus 



Some suiJeromarginals with spines or 

 tubercles 6 



6. Stout acute spine on at least two inter- 



radi al superomarginals. 



Asfroperfen diiplicatus 

 Small obtuse spine on distal half to three, 

 quarters of superomarginals. 



Astropecten articulatus 



III. Key to the Species of Valvatida 



1. Dorsal skeleton reticulate 2 



Dorsal skeleton tabulate or paxillate 4 



2. Disc large, arms short OreorSterreticulatus 



Disc small, amis long 3 



3. Anns triangular in cross section, taper- 



ing to acute ends Narcksia friganaria 



Arms cylindrical. v\'ith rather blunt 



ends Linchla bouvieri 



4. Dorsal skeleton paxillate.- Odontaster hispidus 

 Dorsal skeleton tabulate 5 



5. Large heavy subacute spines on dorsal 



surface Gonuwiter americanus 



No spines on dorsal surface 6 



6. Er more than three to one; arms long, 



acute Media-ster iairdii 



Kr less tlian two to one; arms short, 

 bhmt 7 



7. Papulae few, in rows along each radius ; 



marginals covered with granules. 



Plmthaster dent at us 

 Papulae numerous, scattered among 

 plates; marginals usually bare of 

 granules, at least in center-- PeJta.^ter planus 



IV. Key to the Species of Spinulosida 



1. Arms five 2 



Arms six to eight Solaster caribiaeus 



2. Disc broad, with broadly based arms 



Porania insignis 

 Disc small, with long, cylindrical arms__ 3 



136 



3. Dorsal and marginal plates quadrangu- 



lar, overlapping at corners, in longi- 

 tudinal rows Thyraster serpentarius 



Dorsal and marginal plates not quad- 

 rangular, not overlapping at corners, 

 not in regular rows 4 



4. Small spines in groups or along ridges; 



papulae on both surfaces 



Henricia sanguinolenta 

 One or few coarse spines at nodes; no 



papulae on oral surface 5 



5. Two adambulacral spines 



Echirutster spinvlosus 

 Three adambulacral spines 6 



6. Aboral spines in about five irregular 



rows E chinas f er sentus 



Aboral spines in 9 to 11 rows 



Ech imister hrasiliensis 



V. Key to the Species of Forcipulatida 



1. Aboral surface with short blunt spines 



(tubercles) 2 



Aboral surface with slender spines, at 



least along margins 3 



2. Arms somewhat flattened, shaqily falter- 



ing, with distinct median row of 



aboral pi ates Aster ias vulgaris 



Arms inflated, blunt at tip, no distinct 



median row of aboral plates Asterias forhesii 



3. Aboral spines witli dense wreath of small 



pedicellariae 4 



Aboral spines without dense wreath of 



small pedicellariae 5 



4. With five arms Asterias tanneri 



With ten to twelve armS-_ Coranaster hriaimis 



5. Aboral plates arranged in definite rows, 



one spine to each plate 



Coscin/iisterias tenuispfina 

 Aboral plates not arranged in definite 



rows, more than one spine to each plate 6 



6. Aboral surface with minute spines; 



arms seven to nine-- Stephanasterias gracilis 

 Aboral surface with conspicuous spines ; 

 arms five Leptasterias tenera 



DESCRIPTION OF SPECIES 



The following descriptions are given merely as 

 supplements to the keys and additional aids to 

 identification. It is not the purpose of this paper 

 to give a complete sj'stematic treatment of the 

 Xorth Carolina species of Asteroidea, and diag- 



U.S. FISH AND WILDLIFE SERVICE 



