THE A. LO YON ART A OF PORTO RICO. 
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Family VII. NEPHTHYM. 
(a) Spongodina;, in which the walls between the stem canals have few or no spicules. 
1 . Voeringia Danielssen. 
2. Falla Danielssen. 
3. Barathrobius Danielssen. 
4. Gersemia Marenzeller. 
5. Gersemiopsis Danielssen. 
6. Drifa Danielssen. 
7. Duva Koren & Danielssen. 
8. Eunephthya Verrill. 
9. Ammothea Savigny. 
10. Nephthya Savigny. 
11. Spongodes Lesson, emend. Verrill. 
(6) Siphonogorginah, in which spicules are abundant in the walls of stem canals. 
12. Faranephthya Wright & Studer. 14. Chironephtliya Wright & Studer. 
13. Scleronephthya Wright & Studer. 15. Siphonogorgia Kolliker. 
4. Gersemia. Colony consists of an upright stem with a. few simple branches bearing tufts of polyps 
with nonretractile tentacular regions. Only the body wall of the polyps, the tentacles, 
and the cortical layer of the stem are provided with spicules. 
8. Eunephthya. Colony forms an upright stem, from which accessory branches are given off on all 
sides. These may again branch or give origin directly to tufts of polyps. Polyps are 
large, nonretractile, and covered with thorny club-shaped or branched spicules, the ends 
of which project beyond the surface. These occur only in the cortex of the stem, not on 
the walls of the canals. 
11. Spongodes. Form of colony varies greatly according to the extent of the sterile trunk. Polyps 
are nonretractile. Their heads, containing large spicules, are arched over by tufts of 
large spindle-shaped spicules projecting as spines beyond the polyps. Internal septa not 
furnished with spicules. Cortex of stem and branches contain large spicules. 
Family VIII. HELI0P0RID£. 
Heliopora Blainville. 
Order II. PENNATULACEA . 1 
Unattached polyp colonies having a stalk embedded in the mud or sand and a rachis bearing 
polyps. The stalk generally has an axial rod. 
Section I. PENNATULEA. 
Sea-feathers, with pinnules, rachis with a bilateral arrangement of polyps, elongated, cylindrical. 
I. Pterceidida;. Pinnules well developed, with siphonozoids on the pinnules. 
II. Pennatulidje. Pinnules well developed; siphonozoids on ventral and lateral sides of rachis. 
III. Virgularime. Pinnules small, without a calcareous plate. 
IV. Stylatulid.e. Pinnules small, with calcareous plate. 
Section II. SPICATA. 
Rachis elongated, cylindrical, with a bilateral arrangement of polyps; without pinnules. Polyps sessile. 
V. Funiculinida:. Polyps on both sides of rachis in distinct rows with cells. Ventral siphonozoids 
absent. 
VI. Stachyptilid.e. Polyps (with cells) on both sides of the rachis in distinct rows. 
VII. Anthoptilida:. Polyps on both sides of the rachis in distinct rows, without cells. 
VIII. KoPHOBELEMNONiDiE. Polyps on both sides of rachis in a single series, or in indistinct rows, 
large and without cells; rachis elongated, cylindrical; ventral streak of rachis without 
polyps. 
IX. Umbellulidas. Polyps on both sides of the rachis in a single series, or in indistinct rows, large 
and without cells; rachis short. 
X. Protocaulida;. Polyps on both sides of the rachis in a single series, or in indistinct rows, 
small and without cells. 
XI. Protopti Lidas. Polyps on both sides of rachis in a single series, or in indistinct rows, with cells. 
1 After Sedgwick from Kolliker. 
