130 



calcareous ring is rather thick and pure white. The anterior processes 

 on the calcareous ring are in this species unusually long (Fig. 4. 7), 

 a little longer than the ring itself. The radial processes are per- 

 forated for the nerves, and between all the processes there is a 

 distinct membrane. There are numerous polian vesicles and madre- 

 poric canals. The gonads are branched and the intestine has a 

 loop. On the mesenteries there are numerous cup-shaped ciliated 

 funnels. 



The anchors (Fig. 7. 9) are ca. 300 // long and 240 p wide. 

 The stock is branched and on the vertex there are minute knobs. 

 The anchor-plates (Fig. 6. 7) are ca. 230 [i long and ca. 195 [i 

 wide, and on their exterior surface they have two rows of large 

 knobs around the holes. The articular end with the bridge is some- 

 what varying in shape (Fig. 6. 7 — 9). The miliary granules are ro- 

 settes, which are found all over the skin, and in the tentacles. 

 In the oral disk there are ca. 80 \i long curved rods (Fig. 7. 9), 

 which differ from the rods found in the other species in not being 

 swollen and branched in the ends. 



Oph. grisea is an easily recognized species, which differs di- 

 stinctly from serpentina and variabilis by its pure white calcareous 

 ring. In "The Synaptinae" Clark writes that he has some specimens 

 of grisea with the calcareous ring slightly tinged with green. As 

 all the specimens at hand as well as the present specimens of 

 mauritiae have a pure white calcareous ring, I cannot help sup- 

 posing that if Clark's specimens really have the calcareous ring 

 green, they may perhaps rather belong to another species. From 

 the following species mauritiae the present species differs especially 

 in the shape of the calcareous ring, in the size and shape of anchors 

 and anchor-plates and in the shape of the oral rods. 



Opheodesoma mauritiae n. sp. 



Mauritius. 1874. Andrea. 3 specimens. 



The three specimens at hand measure from 40 to 50 cm in 

 length by 4 — 5 cm in diameter. The colour is yellowish-brown, 

 and the skin is thick and smooth. They have 15 tentacles, and 

 the digits are not united by a web. On account of the thick skin 

 on the oral disk, the eyes are, as in grisea, not visible, but when 



