117 



the anchors is usually unbranched and spiny, but in some of the 

 anchors it is slightly branched, though not so much as in Opheo- 

 desoma. The arms are smooth and on the vertex there are minute 

 knobs. The anchor-plates (Fig. 3. 4-5) measure ca. 700 ^ in length 

 and ca. 350 fi in width. They are more nearly rectangular, but 

 somewhat narrower on the middle than at the two ends. On the 

 middle of the bridge there is a peculiar, large spine. It seems to 

 be rather characteristic as it is present, more or less developed, in 

 nearly all the plates, but its value as specific character cannot be 

 decided by means of a single specimen. Rods are wanting and the 

 miliary granules are rosettes as in maculata. 



This form is very like maculata, but the difference in the shape 

 of the anchor-plates is so great that it will probably prove to be 

 an independent species, but for the present it seems the best to 

 regard it only as a variety of maculata. 



Synapta oceanica (Lesson). 



Holothuria oceanica. Lesson. 1839. Centurie Zoologique, pag. 99, and 

 in Duperry: Voyage autour du monde . . . pag. 9. 

 Synapta oceanica. Jäger. 1833. De Holothuriis. pag. 14. 



„ maculata part. Clark. 1908. The Apodous Holothurians. pag. 78. 



„ „ „ „ 1924. The Synaptinae. pag. 471. 



Tahiti. The Galathea Expedition. 5 specimens. 



The specimens at hand measure from 20 — 48 cm in length. 

 Their colour is bright yellow with a clear brown stripe in the am- 

 bulacra and a dark brown stripe at each side of the ambulacra 

 (Pl. II Fig. 1). They have 15 tentacles, each with 15 — 20 pairs of 

 digits. The digits are united by a low but distinct web. On the 

 oral side of the tentacle-base there is a distinct pigment-spot. The 

 calcareous ring (Fig. 2. 12) is nearly buried in the voluminous 

 cartilaginous ring, and the radial pieces are perforated for the 

 nerves. The madreporic canal is bushy-branched and the numerous 

 polian vesicles are placed all around the circular canal. The gonads 

 are branched and have a distinct main branch. The intestine has 

 a loop, and the anterior end of it is thick and glandular. The 

 ciliated funnels are, as in maculata, placed on the reticulated part 

 of the mesenteries. 



The anchors (Fig. 3. 1) measure ca. 1050 // in length by 750 fi 



