Johnsox.— Polychaeta. 
PLATE 18. 
Fig. 184. Portion of gill of Bispira polymorpha , near base, showing gill-fila¬ 
ments and two eyes. X 30. 
Fig. 185. Double-bordered, capillary seta from abdominal region. X 150. 
Figs. 186-192. Megachone aurantiaca. 
Fig. 186. Thorax, and first somite of abdomen, right side. Collar is clearly 
indicated, x 6. 
Fig. 187. Anterior extremity in end-view, showing regenerating (?) branchiae, 
appressed upon the disc ; their tips point ventrad. X 9. 
Fig. 188. Gill showing filaments, the blood-vessels of which contain oval blood- 
clots. X 26. * 
Fig. 189. Bordered seta, from thorax. X 187. 
Fig. 190. Uncinus from sixth torus. X 150. 
Fig. 191. Uncinus from nineteenth torus. X 275. 
Fig. 192. Uncinus near posterior extremity. X 275. 
