Measurements. — Aperturej , _ 



ART. 14 FOSSIL AND B^GBl^T BRYOZOA CANU AND BASSLER 97 



viously. These tubes are frequently separated from the primitive 

 shell and form floating masses. 



Occurrence. — Gulf of Mexico, Cedar Keys, Florida. Albatross Sta- 

 tion D. 2362, east of Yucatan; 22° 8' 30" N.; 86° 53' 30" W.; 25 fms.; 

 coral sand. 



Cotypes.— Cat. No. 7586, U.S.N.M. 



SCHIZOPODRELLA ISABELLEANA Smitt, 1873 



Plate 27, Figures 1-4 



1873. Hippothoa isdbelleana Smitt, Floridan Bryozoa. Kongl, Svenska Veten- 

 skaps-Akademiens Handlingar, vol. 10, p. 44, pi. 8, figs. 166-168 (not 

 D'Orbigny, 1835). 



f7ia = 0.10-0.12 mm. 



0.13-0.14 mm. 



r, . 1X2 = 0.50-0.60 mm. 

 Zooeciai, _ _„ ^ ._ 



Us: = 0.30-0.45 mm. 



Structure. — The colonies are multilamellar; they encrust algae at 

 their bifurcation and have the aspect of irregularly ramified hollow 

 tubes. The transverse section is not at all that of the Cellepores and 

 Figure 167 of Smitt is perfectly exact. 



The zooecia are rhomboidal or irregular; they are not always well 

 oriented. The ectocyst is rather thick but the tremopores are quite 

 visible by transparency. 



The details of the aperture are quite visible, especially on specimens 

 boiled in Javelle water, and they are identical with those of Schizopo- 

 drella pungens. The poster bears two very small indentations placed 

 symmetrically on each side of the rimule. This character does not 

 exist in the other species of the genus. The aperture is always some- 

 what transverse. , 



The ovicell is porous like the frontal and is never closed by the 

 operculum; it is quite globular, placed on the distal zooecium, which 

 it covers about half. 



On the inferior face of the zoarial lamellae the zooecia have a 

 structure analogous to that which Barroso in 1918 and 1921 observed 

 on ScMzopodrella unicornis Johnston, 1847. The proximal border of 

 each cell is ornamented with four to six very long denticles quite 

 visible by transparency on our figure. Barroso, 1918, figured them 

 viewed from the interior, and he remarks: 



En el angulo que f orman la pared de la base y la parte inferior de las zoecias 

 existen uno surcos, siete de ordinario, separados par pequenas costillas que estdn 

 como reforzando la union de los dos paredes; no puede apieciarse claramente en 

 los citados surcos perforacion, locual las daria significacion de poros de commun- 

 icaci6n interzoeciales.^ 



Barroso, Bol. real Sociedad Espanola de Historia Natural, vol. 18, p. 409 (Sep. 2) (1918). 

 58513—28 7 



