PLATE XXIII. 



Figure magnified -iOO diameters. 



Pact. 



XANTHIDIUM antimipakim, typical form, front view, . . 04 



transverse view of semicell. . 94 



Vat. polymazum, front view, . 94 



lateral view. . . . 94 



XANTHIDIUM k.vsui tlaitm. \'ar. hexagonum, . . 93 



lateral view, . . . 93 



Xanthidium bisenarium, front, side and end view, . 93 



' 10-12. Xanthidium iouleatum, front, side and end view, . 9'2 



13-15. iKTHRODESMua Rauii, front, end and side view, . . 95 



" Iri-lS. A.RTHRODESMUS pragii^e, two front and one end view, . 95 



19-21. .\rthrodesmus con veroens, two front and one end view, 95 



22, 23. variety with short acnlei. . 95 



