Report on the Echinoderms of Noi4h-East Greenland. 



247 



9th joint of a cirrus the two others to the 18th joint of another 

 cirrus, while a fourth specimen was found loose. These specimens are 

 ca. 6— 8 mm long, viz. the stalk ca. 5— 7 mm, the calyx ca. 07 — OSmm 

 long. The number of the stalk joints is 22 — 24. The shape of the 

 middle joints is still quite cylindrical, the primary ring remaining 

 distinct, but scarcely prominent. The longest joints, the 8th— 14th, 

 are 05 mm long, 005 mm wide. The lower joints are somewhat 

 shorter, the 3 — 4 upper ones, as usual, quite short, but scarcely 

 wider than the rest. The basal disk is distinctly lobed (PI. XI, Fig. 2). 



The calyx shows the important difference from the former stage 

 that the radialia (Г) have appeared (PI. IX, Fig. 2). In the stage 

 represented in the figure quoted they are still very 

 small, rhomboidal, lying at the place where the cor- 

 ners of the oralia and basalia meet, these corners being 

 truncated in order to make place for the radial plate. 

 The basalia have grown considerably at their upper 

 end, the oralia somewhat along their lower edge, though 

 not so much as the basalia; on the other hand, it is 

 evident that also the outwards turned edges of the 

 oralia have increased in size, as is seen both from the 

 direct comparison with those of the previous stage and 

 through the fact that a border of regular calcareous 

 meshwork is lining them. 



One of the specimens is preserved with the orals 

 opened and the oral tentacles extended (PI. IX, Fig. 2). 

 It shows that the first sacculus developed is placed on 

 the primary tentacle, the middle one of those three found 

 in each ray. The tentacles contain some irregular, elon- 

 gated calcareous rods (Fig. 2). The tentacles are beset 

 with the usual sensory papillæ; they are not represented 

 here, because in the specimens mounted in balsam, from which the 

 drawings were made, they were invisible. 



One of the four specimens, slightly larger than the three others, 

 is intermediate between stages И a and II b, the radialia I having 

 grown somewhat, and the radialia II have just appeared at their 

 upper end (PI. XII, Fig. 5). Also the anal plate is developed. 



Stage II b. In this stage the Radialia II and III (the axillary) 

 are developed. It is represented by 2 specimens attached to cirri 

 (to the 15th and 17th joint) and 1 loose specimen. The two com- 

 plete specimens are 85 mm long, the calyx being 07 — 08 mm long. 

 The number of stalk joints is 25; the longest joints are 0'5 mm 

 long, 006 -007 mm wide; they have thus become somewhat thicker, 

 and they are now slightly thickened at the ends. The basal disk is 



Fig. 2. Pari оГ 

 a tentacle witli 

 the spicules in 

 natural posi- 

 tion. -"Vi 



