aiHANG IILL K. sv. VKT.-AKAD. IlANDL. BAND 13. AFD. IV. N:0 5. 183 



Reoriilarcs hc placed the huge Echinus esciilentus, which 

 still rcmaius at the head of its now otlierwise limited geuus. 

 By the common fcature of the >>puucta semipcrtusa», the la- 

 cunes of the epistroma, he counocted the two: Echinus glo- 

 bulus and E. sphrcroides, and now it characterises the familv 

 of the Tomnopleuridfe. He strongiy pointed ont, as standing 

 fortli among the rest in close relation, the Echinus saxntilis 

 ond E. I)i;ideinn. and the two nre the nuclcus of our familv 

 of the Diadematidie. And just before them the peculiar aspect 

 of its poriferons zones l(>d liim to place tlie heteropodous Echi- 

 nus Lixula, and iinnie(]iat('ly aftcr them tlie Ecdiinus Cidaris, 

 witli its perforatfd mamelons, wliile tlie tliree concluding sj)e- 

 eies rcprescnt the family of the Echinometra^. Among the 

 Irregulares hc recognised two tvpes, the Spatangida^ and tlie 

 Clvpcastrid;!', and phiccd tliese last, as the most divergent, at 

 tlie fartliest from the Eclvini projier, and witli them ended tlie 

 \vliole series. Tlius lie sent (uit Ins genus Echinus, like so 

 manv others, frauo-ht witli souud o-orms of futme svstematic 

 development. 



