i:6 University of Michigan 



Plate XXVII 



Chondrodesmus rugosior, sp. nov. 



Fig. 187. Tenth keel, x 13. 



Fig. 188. Left gonopod, antedomesal view. X30. 



Zigzvadesmus guiananns, sp. nov. 



Fig. 189. Third, fourth and fifth keels, x 17. 



Fig. 190. Tenth keel, x 17. 



Fig. 191. Thirteenth and fourteenth keels, lateral view, x 17. 



Fig. 192. Anal scale, x 17. 



Fig. 193. Cauda, etc., lateral view, x 17. 



Zigzi'adcsmtis modestus, sp. nov. 

 Fig. 194. Anal scale, x 30. 



