FLORIDAN BRYOZOA. 33 



bryozoa. In accordance with the systematical results there obtained, as based upon 

 the developmental changes of the form of the aperture of the zooecia, here at first I 

 will account for a very interesting species, which scarcely is to be brought, with cer- 

 tainty, under any forraerly constituted genus. I will name it 



Mamillopora. 



Char. gen.: Zooecia escharina formam flustrinam eo imitantur, quod magnam aper- 

 turam, totam fere frontem occupantem, retinent; coloniam Cupularice formse exstruunt. 

 Apertura zooeeiorum formam praebet ellipticam, parte proximali a lateribus constrictam, 

 margine proximali sinuatam. 



Species, quam solam novimus, nominetur 



Mamillopora cupula (Pl. VII, figs. 146 and 147, a — c). 



Char. spec: Apertura zooeeiorum (cujus "longitudo vulgo circiter = 0,18 mm.) 

 margine incrassato circumvallatur, tuberculis rotundatis setarum loco irregulari ordine dis- 

 tributis interdum munito. Vibracularia (?), quae formam zooeeiorum fere imitantur, irre- 

 gulari ordine inter zooecia supra frontem coloniae distribuuntur et supra dorsum (latus in- 

 ferius) coloniae sparguntur. Ooecia tumida poris dense perforantur, frontem saepissime 

 praebent linea longitudinali impressam. 



Hab.: Hane speciem sat frequentem cepit Pourtales ad Floridam e prof. 30 — 68 

 orgyaruin. 



As we do not know more than a single species, it is very difficult to define the 

 limits of the genus, which, perhaps, will show many more modifications. In the ge- 

 nerical character, however, I have quoted the form also of the colonial growth, because, 

 with the almost flustrine form of the zooecial aperture, what seems me very probable at 

 least, may be connected also the Cupularian growth, which more commonly is to be 

 found within the Flustrine series. And, in truth, I regard the Mamillopora as one of 

 the most flustrine states of the Myriozoidan famiry. With a more typically escharine 

 development of this family, I scarcely wait to find it in such an almost flustrine co- 

 lonial form. That the Mamillopora is to be placed here, I think, is proved by the 

 evidently sinuated proximal margin of the zooecial aperture, which character, however, 

 in the worn or overgrown specimens, very easily is evanished; and the great aperture 

 I do not name area, what denomination we used for the flustrine forms, because, not- 

 withstanding its great size, for the most part, in the manner of the Escharines, it is 

 occupied by the operculum. 



Among the formerly constituted genera, the Conescharellina, by D'Orbigny '), 

 perhaps woukl receive the above described species; but his description as well as the 

 figures of the zooecial form make it all too doubtful for here, with any certainty, to 

 adopt that genus. With more surety our Floridan species seems to be allied to the 



') Pal. Franc, 1. c, p. 446, tab. 714, fig-g. 14—16. 



K. Vet. Akad. Handl. B. 11. N:o 4. 



