PALEONTOLOGIC CONTRIBUTIONS 39 



rays meet and the disk begins at their junction, our two specimens 

 show that interbrachial ambital areas are developed to nearly half 

 the length of the rays. They are formed by a skin that is alate to 

 the rays for some distance, giving the interbrachial areas a web- 

 fingered appearance. The margin is strengthened by marginal 

 ambital plates. This feature is also exactly as in Helianthaster. 

 The abactinal area was apparently also covered by a skin in which 

 were embedded numerous subpolygonal to circular plates which 

 are still found scattered over the abactinal disk area of one of the 

 specimens. 



Lepidasterella gyalum (Clarke) 



Plate 10, figure 5 



Through the praiseworthy generosity of Prof. H. P. Cushing, 

 the State Museum has received the counterpart of a beautiful slab 

 with three specimens of a multibrachious starfish, the other side 

 of which is in Cornell University. It is from the Portage near 

 Ithaca, N. Y. This remarkable species was described by Doctor 

 Clarke 1 as H e 1 i a n t h a s t.e r gyalum. In his revision of the 

 Paleozoic Stelleroidea, Professor Schuchert has placed this species, 

 with some doubt, with Palaeosolaster, which belongs in the order 

 Cryptozonia, while Helianthaster is a Phanerozonian, stating : 



That P . (?) g y a 1 urn can not be referred to Helianthaster 

 is therefore seen in the different position of the madreporite, the 

 greater number of rays, the wider ambulacral furrow and the 

 improbability of its having three columns of abactinal ray plates in 

 place of an integument bristling with spines. All of these differences 

 are in harmony with Palaeosolaster. Further, if P. (?) gyalum 

 had interbrachial intramarginals as does Helianthaster, they should 

 show somewhere on these five (three) specimens, all of which 

 preserve the actinal side. While these differences may not appear 

 to be great, they make of Helianthaster a phanerozonian and of 

 Palaeosolaster a cryptozonian. 



A closer study of our slab by means of numerous plasticene 

 impressions, has shown that two of the specimens show their 

 abactinal side, and only the third the actinal side. Peculiarly 

 enough, the two former specimens retain the oral armature and its 

 powerful frame, which is very misleading but happens also in 

 other forms, where the body of the starfish was thin and the frame 

 heavy so that it became pressed through and is then seen on the 



1 N. Y. State Mus. Bui. 121, p. 63. i( 



