NO. 22 CAMBRIAN TRILOBITES, 3D CONTRIBUTION RESSER 29 



ZACANTHOIDES Walcott, 1888 



Zacanthoides weedi, n. sp. 



Zacantlwides sp. Walcott, U. S. Geol. Surv. Mon. 32, p. 465, pi. 65, fig. 3, 

 1899. 



This small form is characterized by its reduced rim and furrows 

 (drawn too heavily in the above cited figure). It is possible that when 

 the pygidium is found it will prove to belong to Prosacanthoides. It 

 is associated with Kootenia. 



Middle Cambrian, Meagher; (loc. I5id) Crowfoot Ridge, Yellow- 

 stone National Park, Wyoming. 



Holotype.—VS.^M. no. 94345. 



