FLOKIDAN BRYOZOA. 81 



Pig. 171; A gToup of younger zooeeia, in the growing edge of the same colony. 



» 172, a and b; The outlines of two different zooscial apertures of this species. in their primary form. 



» 173; Hippothoa biaperta; group of young zooeeia, with the avicularia varying in their shape as well as 



in their size. 



» 174; Part of another colouy, in a higher degree of calcification, provided with ooecia. 



« 175; Some young zocecia of a third colony, with more numerous pores in the zooscial wall. 



u 176; An older part of the same colouy as the preceding figure. 



Plate IX: 



» 177; Hippothoa divergens, part of a colony of the forma läxa. 



At the letter a is shown a zooscion, as it is overgrown by the former, of the same colony as the 



» 178; Gemellipiora eburnea. In its more outgrown state, together with the harder calcification, this colouy 

 has acquired a prolonged form of the proximal part of its zocecia, which, moreover, are very mucb 

 worn. 



» 179; Hippothoa divergens, in its typical form. The plain inner, transverse calcification within the proxi- 

 mal part of the zoceeial aperture nearest will be compared with the same structure in the Hippothoa 

 Isabelleana, as shown by the fig. 166. 



» 180; Cellepora tuberosa, one group of zooeeia, together with spathulate avicularia and with ocecia, which 

 are perforated by pores. 



» 181; Cellepora gigas, one colony in its natural size. 



» 182; Discopora pertusa, two zooeeia from an overgrown colony, as they had covered themselves, seconda- 

 rily, by a continuous layer of chalk över their front side. 



» 183; Cellepora gigas, one zooeeion, together with the aperture of another, at the same degree of magni- 

 fying as usual for the enlarged figures of these plates. 



» 184; The outlines of the distal part of a zooeeion, together with its ocecion. 



» 185; One zooeeion from a colony of the porous variety of the Cellepora gigas. 



» 186; Cellepora coronata, one group of zooeeia, as seen from their upper surface, as they are raised verti- 

 cally from the supporting matter, on which the colony was growing. One of the zocecia is closed. 



» 187; Cellepora m.argaritacea, part of a young branch, with the zocecia still ventricose and. evidently mar- 

 ked from eaeh other by limitar furrows. One of the zocecia shows the four marginal bristles of its 

 aperture. 



» 188; Part of an older branch, with the zooeeia for the most part confluent, as being covered by the com- 

 mon secondary layer of the calcification. The figure, moreover. presents the ooecia and one spathulate 

 avicularium. 



» 189; A still older part of a branch. 



« 190 — 192; The outlines of three different colonies of this species, in their natural size. 



» 193; Cellepora avicidaris, one of its most common colonial forms, as it occurs at Plorida, in its natu- 

 ral size. 



» 194; Group of zooeeia, almost all provided with ooecia, from the younger part of a colony. 



» 195; Some zooeeia and ooecia, from an older part of a colouy, more thickly covered by the secondary 

 layer of calcification. 



» 196; Part of the lateral edge of a colony. 



» 197, a — c; The outlines of three zooscial apertures, b and c in their typical, primary shape. 



» 198; The distal part of a zooeeion, with oral avicularium and ocecion, together with a free, spathulate 

 avicularium of this species, to be compared with the corresponding features of the preceding species 

 (see the fig. 188!). 



Plate X: 



» 199; Escharella Jacotini. the central part of a very young colony, in the more typical eoustitutiou of this 

 species. 



» 200; Part of a more outgrown colony, with the cuiious development of spathulate avicularia, for remin- 

 diug of which I have named this variety Escharella spathulata. 



» 201; Escharella Landsborovii, some zooeeia from a colony which seeraed altogether to want the oral 

 avicularium. 



» 202; Group of zocecia of another colony, with the oral avicularium very constantly developed. 



» 203; Escharella depressa in the Ploridan variety, which 1 have named Escharella. rostrigera; some young 

 zooeeia with persistent pores in their front wall and with the well developed avicularia, in their pro- 

 longed form, varying to their number, one or two on each zooscion. 



K. Vot. Akad. Halldi. B. 11. K:o 4. 11 



