224 MICROPORELLIDiE. 



Chorizopora BrongniartiIj Audouin. 



Plate XXXII. figs. 1-4. 



Flustra Brongniartii, Audouin, Expl. i. 240: Savigny, figj'pte, Pol. pi. x. 



fig. 6. 

 Lepralia tenuis, Hassall, Ann. N. H. ix. (1842), 412: Johnst. B. Z. ed. 2, 



303, pi. liv. fig. 2. 

 Lepralia assimilis, Johnst. B. Z. ed. 2, 304. 

 Lepralia Jacotini, Gray, B.M. Ead. 117. 

 Lepralia Brongniartii, Busk, B.M. Cat. ii. 65, pi. Ixxxi. figs. 1-5 ; Crag 



Pol. 46, pl. vi. fig. 1 : Heller, Bryoz. d. Adriat. Meer. 25 : 



Manzoni, Bryoz. foss. Ital. 2nd Contr. 7, pl. ii. fig. 9 (Sitzb. 



k. Akad. d. Wissensch. Bd. lix. 1. Abth. April-Heft, 1869). 

 MoLLiA TUBERCULATA, D' Orb. Pal. Franc;. Terr. Cret. v. 388. 

 MoLLiA Brongniartii, id. 1. e. 

 ? Eeptesciiarinella riiomboidalis, id, 1. c. 429. 

 Lepralia capitata, Beuss, Bryoz. d. osterr.-ungar. Miocans, 21, pl. iv. fig. 7. 



Zocecia ovate-elongate, somewhat pyriform^ distinct, 

 separated by reticulated spaces or by a single row of 

 interstitial punctures ; surface smooth and silvery, or 

 transversely furrowed ; orifice semicircular, Avitli a thin, 

 very slightly raised peristome, frequently a prominent 

 mucro a little below it ; at the top of each cell a small 

 avicularium with pointed mandible, directed upwards. 

 Ooecia prominent, smooth, subpyramidal, often with a 

 keel in front ; a small avicularium on the summit. 



Colonies forming large, often silvery crusts, with a lobed 

 margin ; frequently assuming a very definite figure. 



Range of Variation. The degree in which the reticulated 

 crust between the cells is developed varies greatly ; and the 

 general appearance of the species is affected accordingly. 

 In many cases the cells seem to lie close together ; but the 

 connecting tubes may be detected towards the margin of 

 the colony. Sometimes they are bordered by a single 

 line of punctures; sometimes a rather wide interspace 

 separates them, filled in by a tubular network and a 

 number of tubercles frequently bearing avicularia. The 



