REPORT ON THE HEXACTINELLIDA. 



415 



PAGE AND PF.Al K 



XXXIX. 



XL. 



XLI. 

 XLII. 



XLIII. 



XLIV. 



XLV. 

 XLVI. 



Acanthascus, F. E. S. 



The dermal skeleton contains exclusively pentacts, 



The dermal skeleton contains pentacts and tetracts, 

 I Isolated pleuralia, ..... 



Pleuralia proj(>cting in groups from small elevations on 

 the external surface, .... 



The autodermalia of the cocoon-shaped body are all 



tetracts {Lanngiwlla, O. Schmidt), 

 Besides the tetract autodermalia many diacts occur 



{Rhahdoralyptiis, F. E. S.), 



Lanuginella, O. Schmidt, with the single species, 



Rhabdocalyptus, F. E. S. 



Funnel-.shapod. Autodermalia exclusively diacts. 



Sack-shaped. Autodermalia are pentacts, tetracts, 

 diacts and monacts, .... 



With great parenchymal hexasters, in which each of the 

 short principal rays bears six long diverging 

 terminals, which gradually increase in thickness 

 towards the round outer end, and are beset all 

 round with backwardly bent pointed hooks 

 (Aulocalij.r, F. E. S.), with the single species. 



Without .such great hexasters, whose long terminal rays 

 increase in thickness towards the round outer end, 

 and are beset all round with backwardly bent 

 pointed hooks {Euryplegma, F. E. S.), witli the 

 single species, ..... 



From the lateral surface of the body long pleural diacts 



project (Caulocah/.i; F. E. S.), 

 The external surface of the body is smootli, 



Caulocalyx, F. E. S., with tlie single species, . 



The oscular margin is not folded back, but remains up- 

 right, surrounding with a sharjj fringe the superior 

 gastral cavity opening of the cup-sbajied body 

 {Crateromorpha, Gray), .... 



The oscular margin is folded back for some distance so 

 that a portion of the gastral surface forms tlie 

 external wall of the body (AuIocJione, F. E. S.), 



XLVII. Crateromorplta, Gray. 



Body (not including stalk), higher than broad, . 

 Body (not including stalk), broader than high, . 



Acunthasem ditbius, 



1 



Acanthascus grossularta, 



Acanthascus cactus, 



XLI. 



XLVII. 



XLVIIL 



1 

 •1 



147 



LVII. 



145 



LVI. 



148 

 r.vii. 



Atdoralyx irregularis, . 174 



LX. 



