Holmes, S.C.A.  <br/><br/>
The periproctal plates of Discoidea 

 - 470-478p.  Illustration 
<br/><br/> Extract<br/>The periproctal plates of three specimens are here described and a comparison made with related genera, the latter including a description of the periproctals of Pseudodiscoidea. 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Periproctal plates<br/>Discoidea