98 



BRITISH PALEOZOIC ASTEBOZOA. 



Table of the English and American Species of the Mesopalj;aster]N/E and 



PlIOMOPALyEASTERlNai. 





Formation. 



R. 



r. 



Remarks. 



Caractacaster caractaci, 



Caradocian 



18-1 mm. 



4"8 mm. 





Gregory, sp. 











Mesopalseaster intevmedius, 



U. Ordovician 



14 „ 



4 



Odontophor as in C. caractaci. Aboiit 20 



Schuchert 





(about) 





infero - marginalia, but only 6 can be 

 seen from the oral surface, while the 

 rest pass on to the sides and distally oven 

 somewhat over to the apical surface. 

 Apical surface unknown. 



„ shafferi, Hall . 



„ 



19 mm. 



3-5 „ 



Holotype of the genus. 



„ primus, n. sp. . 



Ashgillian 

 (U. Ordovician) 



6 „ 



2-25 „ 



See p. 84. 



,, complicatus, 



'. 



8-5 „ 



24 „ 



See p. 87. 



n. sp. 

 ,, finei, Ulrich 



U. Ordovician 



7.5 „ 







Not well preserved. 



„ (?) lanceolatus, 



,, 



4-5 „ 



1-3 mm. 



Large odontophor as in Caractacaster. 



Schuchert 









Ambulacral groove wide and distinctly 

 petaloid. 



„ proavitus. 



,, 



18 „ 



4-5 „ 



Akin to WI. granti. 



Schuchert 











„ (?) wilbera7uis. 



,, 



— 



— 



Not well known. 



Meek and Worthen 











(?) duhixts. 



M. Ordovician 



— 



— 



Not well known. 



Miller and Dyer 











„ (?) antiquus, 



,, 



— 



— 



Not well known. 



Troost 











„ (?) parviusculus. 



L. Silurian 



6 mm. 



2-5 mm. 



Apical surface unknown. Oral surface as 



Billings 









in M. primus. 



„ (?) leintwarden- 



,, 



— 



— 



See p. 89. 



sis, n. sp. 











(?)sp. . . 



,, 



— 



— 



See p. 90. 



„ (?) calaraden- 



,, 



9 mm. 



3 mm. 



Closely related to M. (?) parviusculus, but 



sis, Schuchert 









differs in being larger with more plates in 

 the columns. Only the oral side known 

 (Schuchert, p. 89). 



,, granti, Spencer 



" 



16 „ 



5 „ 



Supero-marginals carried well within the 

 walls of the disc. 



„ bellulus, 



M. Silurian 



— 



— 



Related to M. granti. 



Billings 











„ (?) acuminatus, 



L. Devonian 



17'o mm. 



8.5 mm. 



Possibly an end member of a lineage. 



Simonovitsch 











(?) ClarM, 



U. Devonian 



24 



5-8 „ 



Schuchert remarks (p. 95) : " This clearly 



Clarke and Swartz 





(aboixt) 



(about) 



determined species is a late survival of 

 early Palaeozoic primitive asterids. The 

 characters, so far as determinable in the 

 natiiral mould, are those of Mesopalse- 

 aster, but as the disc skeleton is not pre- 

 served, it is very probable that when this 

 feature is known the form will be seen to 

 belong to a new genus." 



Spaniaster latiscutatus, 



L. Devonian 



11 mm 



4 mm. 



— 



Sandberger 











Miomaster drevermanni, 



,, 



35 „ 



8 



— 



Schondorf 











Devonaster eucharis, Hall 



M. Devonian 



40 „ 

 (from Schvi 



11 „ 



chert's fig.) 



— 



„ rhermingensiy. 



U. Devonian 



59 mm. 



11 nmi. 



— 



Schuchert 





(from Schu 



chert's fig.) 





I'romnpalseaster uilsoni, 



M. Ordovician 



37'5 mm. 



10 mm. 



Seep. 91. 



1 Raymond 











„ iJceriMniiMS, 



„ 



30 „ 



7 „ 



Schuchert regards this species as ancestor 



Schilchert 









of P. speciosus. 



„ sp. undet. (see 



U. Ordovician 



22 „ 



4 „ 



Schuchert regards this as probably the 



] Schuchert, op. cit. p. 108) 



1 



1 









young of P. speciosus. He remarks with 

 respect to a still smaller specimen that " It 

 has but a single axillary plate in each 

 interbrachial area and about 15 adambu- 

 lacrals in a eohimn. It is interesting to 

 note that in these young individuals of 

 Fromopalseaster, the smaller they are the 

 more they approach Mesopalxaster and 

 suggest Hudsonaster." 



