The Bryozoa of the Tortiigas Islands, Florida. 205 



Genus Schizoporella Hincks, 1880. 



Schizoporella unicornis (Johnston). 



Johnston, 1847, p. 320 {Lepralia unicornis). — Desor, 1848, p. 66 (Lepralia vari- 

 olosa). — Leidy, 1855, P- 10 (Escharina variabilis). — Smitt, 1873, p. 44 (Hip- 

 pothoa isabelleana). — Verrill and Smith, 1873, p. 713 (Escharella vari- 

 abilis). — Verrill, 18756, p. 41 {Hippothoa variabilis); ibid., p. 41, pi. ill, 

 fig. I {Hippothoa reversa, n. sp.); 1878, p. 305 {H. variabilis); 1879b, p. 193, 

 and 1880, p. 30 (Escharina isabelliana d'Orbigny, E. reversa Verrill and 

 E. ansata Gray); 1900, p. 592 (? Schizoporella isabelliana). — Levinsen, 1909, 

 p. 323.— Osburn, 1912, p. 236. 



Abundant from low water to 10 fathoms, in the drift and growing 

 profusely on the piles of docks, incrusting shells, and coral rockb, and rising 

 into branched, finger-like processes about worm-tubes and the stems of 

 hydroids, or occasionally growing free. Masses nearly as large as a man's 

 head were dredged. The color varies from white or pale pink or purple in 

 young, rapidly growing colonies, to a dark purplish red or sometimes nearly 

 black. Colonies 1.5 inches in diameter were found incrusting the bottom 

 of a skiff that had been in the water only from May i to June 23. 



Smitt recorded the incrusting form "growing in a single layer of whitish 

 and yellowish hue on Ocidina and Nullipora at the depth of 42 fathoms," 

 and, "a more compound colony, composed of several concentric layers of a 

 purplish-blue tint, around an axis of foreign matter," at a depth of 17 

 fathoms. 



Schizoporella floridana n. sp. (Figs. I 7 and 18.) 



Primary characters of the zooecium much like those of S. unicornis 

 (Johnston) but with a slightly more V-shaped sinus; avicularia situated far 

 forward, often in advance of the middle of the orifice, and with the mandible 

 usually strongly curved toward the zooecial axis; large vicarious avicularia 

 with long-pointed, straight mandibles on hemispherical cells raised high 

 above the surface of the colony. 



The naked-eye appearance of the colonies is very similar to that of 

 S. unicornis (Johnston) and the general characters of the zooecia are not 

 very different from that species. It does differ remarkably, however, in 

 the presence of the large, vicarious avicularia, which are sometimes very 

 abundant. These are raised high above the surface of the colony as rounded, 

 knob-like prominences; the mandibles, while broad at the base, are very 

 much narrowed and elongated distally. These are turned in all directions 

 on the colony without any apparent arrangement. Schizoporella ampla 

 Kirkpatrick, from Mauritius, and 5. viridis Thornley, from the Red and 

 Mediterranean Seas, also have vicarious avicularia. 



The ordinary avicularia are situated at the side of the orifice and the 

 mandibles are curved toward the axis of the zooecium so as to nearly con- 

 form to the curve of the margin of the orifice. There is much variation in 

 this avicularium and the mandible is occasionally straight instead of curved, 

 and it may be directed backward or sideways. It is usually situated well 

 forward near the anterior border of the orifice, but may be placed farther 



