d7C COMATUr.lDAE. 



II. Rays well separated. 



Lower pinnules slender . 6. elongata. Mus. 

 /3. Later cirrhus-joints not spiny. Leyd. 



I. Pinnule on sixth brachial 

 larger than that on fourth 



brachial 7. himaculata. 



II. Pinnule on fourth brachial 

 larger than that on sixth 

 brachial. 



1. Lower pinnules not specially 

 stiff. 



Smooth wedgeshaped arm 

 joints with forward projec- 

 tions alternately on opposite 

 sides. 



a. Second radials much lon- 

 ger at sides than in the 

 middle. Rays in close con- 

 tact; outer joints of pri- 

 mary arms flattened later- 

 ally 8. hremcuneata. 



b. Second radials scarcely 

 longer at sides than in the 

 middle. Rays well sepa- 

 rated 0. laevicirra. 



2. Lower pinnules stiff" and sty- 

 liform. 



Arm-joints bluntly wedge- 

 shaped' without forward pro- 

 jections 10. splcata. 



n. Mouth more or less excentric ; anus 

 subcentral. 



No sacculi at sides of ambulacra. 

 Oral pinnules provided with termi- 

 nal combs Genus Actinometra Mull. 



A. Second and third radials united 

 by syzygy. 



IN'ote.s frona the Ijeyden ïMii-«euin, Vol. III. 



