4 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 85 



MISKOIA Walcott 1911 ' 



MISKOIA PLACIDA, new species 



Plate 2, fig. I 



Comparing this form with M. preciosa Walcott, the genotype, the new species 

 is stouter and shorter. As none of the specimens referred to the type species 

 preserves the rear end, it is not possible to determine whether the lobate termi- 

 nation of M. placida is also characteristic of the first species. The annulations 

 of the body are clearly marked in the specimen illustrated, particularly on the 

 counterpart, which is a mold of the exterior. Teeth are shown around the mouth 

 as bright, shiny, curved, chitinous hooks. 



Holotype.—V. S. N. M., No. 83928. 



CANADIA Walcott 191 1 

 CANADIA SPINOSA Walcott 



Plate 4; plate 5; plate 6, figs. 1-2 



Canadla spinosa Walcott, 1911, Smithsonian Misc. Coll., vol. 57, no. 5, p. 118, 

 pi. 23, figs. 4-7. 



Original description. — " Body slender, formed of 20 to 21 segments 

 that, when flattened on the shale, are a little longer than wide ; each 

 segment has a pair of parapodia with a dorsal and ventral bundle of 

 strong non- jointed setae. The setae are finely illustrated by figures 4, 

 6, and 7. Head minute, with a pair of large tentacles curving outward 

 from the front anterior margins ; a bundle of fine setae occurs on 

 each side of the head back of the base of the large tentacles. A 

 straight slender enteric canal is indicated on several specimens. Mouth 

 and anus not seen, but probably at or near the end of the annelid. 



" Diwensions. — The largest adult specimen has a length of 34 mm., 

 with a width of the body at the seventh segment from the head 

 of 1.5 mm." 



Fortunately many additional specimens of this interesting spiny worm were 

 found after 1911. Those first illustrated give a fairly good conception of the 

 general features ; however, illustrations of additional specimens may show 

 features particularly desired by the biological student at places where the other 

 specimens are faulty. 



Ples'wtypes. — 'U. S. N. M., Nos. 83929a-e. 



^Walcott, C. D., Smithsonian Misc. Coll., vol. 57, no. 5, p. 114, pi. 18, figs. 

 1-5. iQii- 



