Plate HI. 



Fig. 33. Pavonaria fiumarcliica (M. Sars), young (i-Microptilum,-) stage, from the ventral side, x 2. 



(The specimen No. 3, p. 40). The zooids are not represented in the figure; they can scarcely 



be seen with this enlargement; the bodies looking like zooids are young polyps. 

 Fig. 34. Id.: the upper part of the pen of another specimen (No. 2, p. 40), from the ventral side, x 3. 



a are quite young polyps, / the conical end of the stem. 

 Fig. 35. Id.: the lower part of the rhachis of the same specimen as in the preceding figure, a young 



polyps; x 3. 

 Fig. 36. Id.: the lower part of the pen of the same specimen as figs. 34 and 35, seen in profile from 



the left to show the Micr opt Hum-character; comp. the lower part of the pen of Kollikers figure, 



Chall. Rep. PI. VII, Fig. 27 b, of Microptilum •willemoesii. 

 Fig. 37. Umbellula lindahlii K611., young specimen, seen from the left, natural size; from Davis Straits 



(see p. 75). 

 Fig. 38. The same specimen; the primary polyp, x 8; most of the tentacles torn off; at k part of the 



upper end of the calcareous axis shines through; p bud of a new polyp; z zooids. 

 Fig. 39. The same specimen; the lower part of the rhachis, with zooids z, and peduncle; x 8. 

 Fig. 40. Umbellula lindahlii, young specimen, natural size; the cluster seen so much from the dorsal 



side, that P, the terminal or primary polyp, is distinctly seen. 

 Fig. 41. The same specimen, natural size; the cluster is seen from the ventral side. 

 Fig. 42. The same specimen, part of the cluster, x 3, seen from the ventral side to show the tentacle 



of the zooids, and that the ventral tentacle v of the small polyp is larger than the others. 

 Fig. 43. The same specimen; the lowermost part of the stalk, x 6; shows zooids with fine tentacles; 



some zooids have a tentacle with lateral branches (t). 

 Fig. 44. The same specimen; a group of spicules from the lower end of the peduncle; enlargement: 



Zeiss, Obj. apochr. 8.o mm , Comp. ocular 4, length of tube i6o mm . 

 Fig. 45. The same specimen; spicules, under higher magnifying powers. Zeiss, Obj. apochr. 8.o mtn , Comp. 



ocular 12. 

 Fig. 46. Umbellula encrinus (L.). The cluster of a young specimen (No. 1, p. 80), seen from the rudiment- 

 side (the ventral side), x 3; P the primary polyp; t tongue-shaped zooid-area. 

 Fig. 47. The same species; another specimen, young stage; natural size (No. 2, p. 80), from the right 



side of the terminal polyp. P the terminal polyp; z large zooid; a rudiment of a polyp; 1, 2 



the two polyps on the right side of the terminal polyp; dt the dorsal zooid-belt reaching up 



to the base of the body of the primary polyp. 

 Fig. 48. The same specimen as in the preceding figure; part of the cluster, x 3; dt, P. 1, 2 as in the 



preceding figure; t the three tongues of zooids on the left side. 

 Fig. 49. The same specimen as in figs. 47 — 48; part of the cluster, seen from the rudiment-region (the 



ventral side), x 3. P, 1, 2, dt as above; a rudiments of four polyps; between these rudiments 



stripes of zooids shoot up, the first rudiments of zooid-tongues. 

 Fig. 50. Umbellula encrinus; a large zooid from the inner part of the cluster of a fully formed, large 



specimen, enlarged (of No. 7, p. 80); t tentacle with lateral branches; m mouth. 

 Fig. 51. Id.: spicules from the lower end of the peduncle (of the specimen No. 10, p. 80). Zeiss: Obj. 



apochr. 8.o mm , Comp. ocular 12, length of tube i6o mm . 



Figs. 37, 38, 44, 45, 50 and 51 drawn by the author, the others by Th. Bloch. 



