136 



are smaller and their ends neither swollen nor branched. They 

 measure 80 — 4 60 ^ in length. 



This species is the nearest related to lappa (Johs. Müller) but 

 the differences in the shape of the anchor-plates, the calcareous ring 

 and the oral rods separate it distinctly from that species. 



In the tissue around the calcareous ring and the water-vascular 

 system there are in some of the specimens some small cysts, 

 which evidently are of patalogical nature. When these cysts are 

 present in the tissue around the calcareous ring, they often produce 

 so great deformities of the ring, that the characteristic shape is 

 hardly recognizable. 



Euapta lappa (Johs. Müller). 



Synapta lappa. Johs. Müller. 1850. Müllers Archiv, pag. 134. The 

 figures of the calcareous deposits are found in Johs. 

 Müller: Ueber den Bau der Echinodermen, 1856, Pl. 

 VI fig. 17 and Pl. IX fig. 4. 

 Euapta lappa. 0stergren. 1898. Das System der Synaptiden, pag. 1 13. 



— Clark. 1908. The Apodous Holothurians, pag. 73 Pl. IV 

 fig. 23—25. 



Non : Euapta lappa. Clark. 1 924. The Synaptinae, pag. 464 Pl. I fig. 5—7 

 St. Thomas. Krebs. 1 specimen. 

 St. Croix. Benzon. 2 specimens. 

 Christianssted. 10.1.1906. 1 specimen. 



The largest specimen at hand, that from Christiansted, measures 

 55 cm in length. The colour is yellowish and the skin is thick 

 and slimy. All the specimens have 15 tentacles each with ca. 20 

 pairs of digits, which are united by a web. On the oral disk there 

 are eye-spots. The cartilaginous ring is wanting. The calcareous 

 ring (Fig. 9. 4) is green and the radial pieces are perforated for 

 the nerves. There are no processes on the anterior edge of the 

 ring. There are many polian vesicles and a single madreporic 

 canal. The gonads are branched and the intestine has a loop. On 

 the mesenteries there are ciliated funnels of the common size and 

 shape. 



The anchors (Fig. 10. 5) measure ca. 350 /a in length by ca. 

 200 fi in width. The stock is branched and on the vertex there 

 are minute knobs. The anchor-plates (Fig. 10. 6) measure ca. 260 pu 



