PLATE 43. 



PORODISCIDA. 



Fig. 1. Rhopalastrum malleus, n. sp., 



Fig. 2. Rhopalastrum ypsilinum, n. sp... 



Fig. 3. Rhopalastrum hexaceros, n. sp., 



Fig. 4. Rhopalastrum triceros, n. sp., 



Fig. 5. Rhopalastrum trispinosum,ii. sp. (vel Dictyastrum trispinosum), 



Fig. 6. Rhopalastrum arcticum, n. sp., 



Fig. 7. Rhopalastrum hexagonum, n. sp. (vel Dictyastrum hexagonum), 



Fig. 8. Rhopalastrum irregulare, n. sp., 



Fig. 9. Euchitonia ktnceolata, n. sp., . 



Fig. 10. Euchitonia carcinus, n. sp., 



Fig. 11. Euchitonia echinata, n. sp., 



Fig. 12. Euchitonia stohrii, n. sp., 



Fig. 13. Hymeniastrum euclidis, n. sp., 



Fig. 14. Chitonastrum jugatum, n. sp., 



Fig. 15. Chitonastrum lyra, n. sp., 



A living specimen observed. The entire shell is enveloped by the calymma 



and surrounded by radiating pseudopodia (drawn much too short). ' 



Between the two paired arms arises a large " sarcode-flagellum." The 

 central chamber and the first enveloping ring are filled by the clear 

 nucleus ; the other rings and all the chambers of the arms contain 

 numerous pink oil-globules. 



Fig. 16. Trigonastrum regular e, n. sp. (vel Chitonastrum regulare), . x 200 539 





Diam. 



Page 



X 



100 



527 



X 



50 



528 



X 



100 



529 



X 



50 



529 



X 



150 



525 



X 



300 



529 



X 



100 



525 



X 



100 



528 



X 



80 



534 



X 



300 



535 



X 



120 



536 



X 



100 



534 



X 



200 



531 



X 



200 



537 



X 



500 



538 



