30 



LARVIFORM CRINOIDS 



At the same time he introduced the family Embryocrinidae based upon the 

 new genus Embryocrinus [14, p. 130]. 



In 1920 Wanner discussed in detail the relationships of the various 

 members of the Hypocrinidae [15]. At this time he abandoned the Embryo- 

 crinidae and added to the Hypocrinidae the following genera. Embryocrinus 

 Wanner, Lageniocrinus de Koninck and Le Hon, Coenocystis Girty and the 



COENOCYSTIS 



I 



further displacement 



of orals and anal opening 



ACARIAIOCRINUS HEMISTREPTACON 



atrophy of radial3 atrophy of radlals 

 displacement of orals and displacement 

 of orals and anus 



ATREMAC3INU3 



anchylosis of 

 basals and 



' 1 lnfrabasals 



I I 



TENAGOCRINTJS CRAN0CRINU5 EMBRYOCRINUS LAGENIOCRINUS 



Permian Period 



Pennsylvania!! Period 



migration of brachial 

 muscle fields to orals 



TYTTHOCRrNUS 



atrophy of radlals 



LAGENIOCRINUS 



1 



atrophy of radlals 

 and anal opening 



AMPHIPSAI.IDOCRINUS 



DICHOSTREBLOCRINUS 



1 



atrophy of radlals 

 displacement of orals 

 in opposite direction 



atrophy of arms 

 dwarfing of radlals 



dwarfing of arms and radlals 

 displacement of anal opening 



Fig. 4 



new genera Metasycocrinus and Abrachiocrinus based upon previously de- 

 scribed species. In 1923 two more new genera. Allosycocrinus and Acariaio- 

 crinus were added to the Hypocrinidae [16, p. 133 ff]. 



In a more recent paper Wanner has further expanded this interesting 

 family by the addition of Hemistreptacon Jakovlev and the new genera 

 Tenagocrinus, Cranocrinus, and Atremacrinus [17, p. 84 ff]. 



