38 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 85 



HELMETIA Walcott 1918 



HELMETIA EXPANSA Walcott 



Plate 27 



Helmetia expansa Walcott, 1918, Smithsonian Misc. Coll., vol. 68, no. 12, p. 7, 

 fig. 8. 



This is another of the species first published in the Smithsonian explorations 

 pamphlet for 1917, and for that reason is here reprinted. 

 Holotype.—U. S. N. M., No. 8395^- 



EXPLANATION OF PLATES 

 Plate i 



PAGE 



Margaretia dorns, new species 2 



Fig. I. Impression of outer surface. 



2. A wider and less well defined specimen. Possibly a mutilated 



fragment. 



3. Impression of surface, on which the elevations apparently were 



more conical and more numerous, which may indicate another 

 species. 



4. Unretouched photograph by reflected light of the typical form. 



This is again the impression of the outer surface. Compare 

 the elongate elevations with the more conical ones in fig. 3. 



5. Unretouched photograph of the holotype. 



6. (X 2.) Another, less perfect specimen on which Doctor Walcott 



apparently laid stress. 



Plate 2 



PAGE 



Miskoia placida, new species 4 



Fig. I. The holotype showing the annulations, the teeth around the 

 mouth, and the manner in which the digestive tract seems to 

 run along one side of the body, as it is compressed in the 

 shale. 



Redonbtia polypodia Walcott 3 



Fig. 2. A specimen, possibly of a different species, since it has smaller 

 appendages. Parts of a Hymenocaris? lie above it. 

 3. (X 1-5.) Holotype, as illustrated previously. 



Plate 3 



PAGE 



IVizvaxia corrugata Walcott 6 



Fig. I. Photograph of a very fine individual retouciied to bring out the 

 striae on the scales. 



Portalia mira Walcott 3 



Figs. 2, 3. Counterparts of the holotype. A specimen of Miskoia lies 

 nearby. 



