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Nils Rosén 



beach at same places. A little further out from the Mangrove growth several lagre 

 crabs occur, some af them being identical with those met with along the rocky 

 shore. Fishes as Gerres, Gohius, Spheriodes, Eucinostoiims and other are often rather 

 numerous here. 



The coral reefs. Corals are scattered over vide areas of the Bahamas. They 

 are mostly found along the edges of the banks but also in the interior of them. 

 The vast surface of the Great Bahama Bank east of Andres is quite devoid of corals 

 except at a few places just along its edge, but along the eastern edge of this island 

 the corals flourish forming magnificent barrier reefs. Several other rather extensive 

 coral reefs are found along the Providence channels. The corals seem always to 

 form only a thin layer on isolated patches of seolion rock, the material of which 

 the whole archipelago is built up, if not consisting of not yet consolidated coral 

 sand. Madreporas, Porites and Masandrinas are the main forms of corals on the 

 reefs. On the reef along the eastern coast of Andos the palmaUi form of the 

 Madreporas were generally found on the outer part of the reefs, while eervicornis 

 forms occurred on the inner edge, as well as in many of the bights. Forms of an 

 intermediate shape were often observed on the tops of rock patches lying inside 

 those with true palmata forms. Besides corals, Millepores and a great number of 

 different Gorgonians, as well as sponges, make up the reefs. A very rich and 

 various animal hfe dwells about the reefs. Numerous crabs and shells crawl among 

 the corals, gorgonians and sponges. Boriiag mussels are common. Worms and 

 ophiurians occur in many forms. The animals that always must attract the greatest 

 attention of every visitor to a coral reef are the fishes. Their brilliancy of colours 

 is surpassed by no other animals. Some of the most striking forms of fishes occurring 

 about the coral reefs of the Bahamas may be mentioned: Scants ccerideus (Blocft), 

 Ghlorichthys bifasciatus (Bloch), Iridio garnoti (Cuv. & Valene.) Teuthis coeruleits 

 (Bloch & Schneider), Pomacanfhtis arcuatus L., AngeUchthys ciliaris L., Ocyuriis 

 chrysurus (Bloch), several species of Bodianus and Epineplielus. For a further 

 account of the fish fauma I refer to the third part of this paper. 



The fauna of the sea between the reefs and the shore. The fauna is almost 

 quite concentrated on the reefs. Between the reef and the shore in some places 

 gorgonians and a few corals may be found, but as a rule, the only animals that 

 are found in this part of the sea are a large holothuria [Holothuria mexicana), the 

 sea-star Pentaceros reticulatus, the shell Strombus gigas and sponges. In the holothuria 

 named Fierasfer affinis dwells and in the mantle cavity of Strombus gigas another 

 symbiotic fish will be found, Apogonichthijs strombi Plate. In the holothuria I also 

 found a parasitic gastropod, living in the water-lungs, Megadenus holothuricola, which 

 I have described in an other paper Almost all orders of marine animals are found 

 in the labyrinths of the sponges : worms, crustaceans, molluscs, ascidians, fishes and 

 so on, and a fauna quite as rich inhabits the dead shells of Strombus gigas. Of 



^ EosÉN, Zur Kenntnis der parasitischen Schnecken. Fysiograf. Sällskapets Handl. Lund 1910. 



