xxxvi THE VOYACxE OF H.M.S. CHALLENGER. 



Family II. Zoroasterid^e, Sladen, 1888. 



Cryptozonate Asterids with contingent marginal plates. Disk small ; rays long, 

 cylindrical, and tapering. Abactinal skeleton tessellate, arranged in regular longitudinal 

 and transverse series. Primary apical plates persistent in the adult. Tegumentary 

 developments spiniform (long and needle-like). Adambulacral plates unequal, alternate 

 plates with prominent ridges. Adambulacral armature complex, polyacanthid. Pedi- 

 cellariae (forcipulate) pedunculate. 



Genus 1. Zoroaster, Wyville Thomson. 

 Genus 2. Cnemidaster, n. gen. 

 Genus 3. Pholidaster, Sladen. 



Family III. Stichasterid^e, Perrier, 1885. 



Cryptozonate Asterids with contingent marginal plates. Abactinal skeleton tessellate, 



arranged in more or less regular longitudinal series. Tegumentary developments spiniform 



(equal and papilliform or granuliform). Adambulacral 'plates small, equal, compressed, 



with no ridges. Adambulacral armature simple, diplacanthid . Pedicellarise forcipiform 



and forficiform. 



Genus 1. Stichaster, Midler and Troschel. 



Genus 2. Neomorphaster, n. gen. 



Genus §. Tarsaster, n. gen. 



Family IV. Solasterid^e, Perrier, 1884. 



Cryptozonate Asterids with a reticulate abactinal skeleton, more or less irregular, with 

 plates bearing paxilliform groups of spines. Actinal intermediate plates more or less 

 developed. Armature of the adambulacral plates pectinate, all with a transverse series, 

 some with a second series at right angles to this, parallel to the furrow. AVith inter- 

 brachial septa. No supradermal membrane. No pedicellarise. 



Subfamily 1. Solasterin.e, Sladen, 1888. 



Solasteridse with the armature of the adambulacral plates in two series at right angles 



to each other. 



Genus 1. Crossaster, Miiller and Troschel. 



Genus 2. Solaster, Forbes. 



Genus 3. Lophaster, Verrill. 



Genus 4. Rhipidaster, n. gen. 



