A MONOGRAPH OF THE EXISTING CRINOIDS 81 



Series III: IIBr series 2; more than 10 arms: 



5. All division series 2; first brachial syzygy between 



brachials 1 +2 Stelligera group. 



6. IIBr 2 ; first brachial syzygy between brachials 3 + 4 _ Valida group. 

 Series IV: IIBr series 4 (3 + 4): 



7. IIBr series 4 (3 + 4): IIIBr series 3 (2 + 3); first 



arm pinnule on the first brachial, and a syzygy 



between bracluals 2 + 3 Fimbriata group. 



8. IIBr series 4 (3 + 4); first arm pinnule on the second 



brachial, and a syzygy between brachials 3 + 4 Parvicirra group. 



In 1 907 the present author established the family Actinometridae, including the 

 genus Comatula used as the equivalent of Actinometra as employed by Carpenter. 



Since Actinometra is a pure sjnonym of the earlier Comatula, both having as the 

 genotype Comatula Solaris, the name Actinometridae was changed in the following 

 year to Comasteridae. 



The family Comasteridae as understood in 1908 included the genera Comatula 

 and Comaster. The generic name Comaster was taken as the basis for the family 

 name, since Comatuladae or Comatulidae had been used with various meanings 

 since 1828. 



Note. — For keys to the subfamilies included in the family Comasteridae see p. 69. 



ARTIFICIAL KEY TO THE GENERA OF THE FAMILY COMASTERIDAE 



a'. Ten arms only. 

 bK Cirri present. 



c'. All of the pinnules present. 



^d'. Combs with more than 3 teeth; cirri not excessively slender with excessively elongated 

 segments; arms more than 20 mm. in length, 

 e'. Comb confined to the distal portion of the proximal pinnules, never extending basal- 

 ward so far as the middle; teeth of the combs little, if any, higher than the width 

 of the segments that bear them; no spinous median knobs or keels on the earlier 

 brachials. 

 /'. Several of the distal cirrus segments preceding the penultimate bear each a dorsal 

 tubercle, spine, or transverse ridge. 

 g'. Outer cirrus segments carinate dorsally and with a dorsal tubercle or small spine; 

 distal ends of the basal segments of the lower pinnules not markedly enlarged. 

 hK No conspicuous carinate processes on the first and second segments of the 

 proximal pinnules (Seychelles, Amirante Islands, the Red Sea, and Ceylon to 

 tropical Australia, the Bonin Islands, southern Japan, the Philippines, and 



Macclesfield Bank; 0-9S4 meters) Comissia. p. 244. 



li'. First and second segments of the proximal pinnules with a very high and promi- 

 nent carinate process of which the outer edge, at least on the second segment, 

 is parallel with the longitudinal axis of the pinnule (Caribbean Sea and Gulf 



of Mexico; 0-479 meters) Leptonemaster, p. 275. 



g-. Outer cirrus segments not carinate dorsally, each bearing dor.sally a straight trans- 

 verse ridge; distal ends of the basal segments of the lower pinnules with greatly 

 flaring spiny distal ends which project as rough spurs on the aboral side (Bass Strait 



and the coast of Victoria; 119 [?91]-183 [?311] meters) Comanthoides, p. 240. 



p. No dorsal processes on the outer cirrus segments except for the opposing spine on the 

 penultimate segment; cirrus segments more or less subequal. 

 S'. Less than 25 cirrus segments, of which at least some, and commonly all but the 

 first 2, are longer than broad. 



