20 
THE VOYAGE OF H.M.S. CHALLENGER. 
Habitat . — Zanzibar (Selenka), Mauritius (Haacke, Ludwig), Indian Ocean (Ludwig), 
Celebes (Jaeger), Society Islands (Selenka), Philippine Islands (Semper), Ualan in 
Caroline Islands (Brandt), Nicobar Islands (Semper), 
(Mus. Holm.) Several specimens from Navigator Islands, Tahiti, Eimeo, Mauritius, and 
Goonong. One dredged at Tahiti seems to be Selenka’s Synapta agassizii, 
distinct from the typical form by possessing five darker longitudinal bands. 
2. Anchor-plates symmetricol, with six to seven larger dentate holes. Madreporic 
canals simple. 
a. Cartilaginous ring present. 
Synapta vittata (Fistularia) , Forskaal, 1775 ; Jaeger, 1833 ; Blainville, 1834 ; J. Miiller, 
1854 ; Held, 1857; Herapath, 1865; Ludwig, 1882. Tiedemannia vittata, 
Leuckart, 1830, 
Body with a series of protuberances along the five broader whitish longitudinal bands 
(according to Forskaal). Cartilaginous ring present (according to Muller). 
Anchors with smooth arms, and anchor-plates with six larger dentate holes and 
three slightly smaller and some minute smooth holes (according to Ludwig). 
No fully satisfactory description is given. 
Habitat . — Bed Sea (Forskaal, Gray, Efippel, &c.). 
Synapta nigra, Semper, 1868, 
Digits of the tentacles united by a web at their base. Numerous Polian vesicles. 
A single madreporic canal. Cartilaginous ring posteriorly with small holes. 
Anchor-arms smooth. Anchor-plates with six large dentate holes and three 
slightly smaller and some minute smooth holes. Miliary granules resembling 
incomplete rosettes. 
Habitat . — Bohol (Semper). 
h. Cartilaginous ring absent. 
Madreporic canals numerous. 
Synapta glahra. Semper, 1868 ; Ludwig, 1881, (?) Oncinolabes mollis, Brandt, 1835. 
Digits of the tentacles united by a web as far as their middle. Body with round 
protuberances, like those in Synapta beselii. Numerous Polian vesicles. Anchor- 
arms smooth. Anchor-plates with seven large dentate holes and some small 
smooth ones at the handle ; the seventh large hole is only partly dentate. 
Miliary granules — scattered rosettes. 
Habitat . — Bohol (Semper), (?) Guahan in Marianne Islands (Brandt). 
