ON CIIETACEOUS POLYZOA. 315 



1850. Genus Vincdlaria, d'Orb., ' Terr. Cret.' (Not Defrance.) 



This is by no means a satisfactory genus to deal with in the fossil 

 state, or at least with those species which are found in the British Chalk. 

 In a former report (1884 •), on pp. 106-110, under the family term 

 Cellarid^, Hincks, I hav^e already discussed the probable relationship of 

 Vincularia species. In Mr. Waters' various papers species of Vincularia 

 are relegated to either Membranipora or Micropora ; but I note that in 

 Miss E. C. Jelly's Synonymic Catalogue three of d'Orbigny's recent 

 species are retained under the genus Vincularia (p. 271). In their joint 

 paper (' Bryoz. de Faxe' ^) Messrs. Pergens and Mennier retain the generic 

 term Vincularia for species found in the debris of the Eaxoe limestone of 

 Denmark, and Dr. Marsson in his Biigen monograph also adopts this 

 genus. In all probability in future classifications the genus will be 

 disallowed, but no useful purpose would be served, so far as I can judge, 

 in wholly suppressing the generic term in the present report on the 

 Polyzoa found in the British Chalk. For the present, therefore, I retain 

 the genus Vincularia for all those forms which are closely related to, 

 or characteristically identical with, French ' Bryozoan ' forms as described 

 in the text and figured in the atlas of d'Orbigny. 



85. Vincularia (Cellaria) cactiformis, d'Orb., ' Terr. Cret.,' p. 29, pi. 



651, figs. 1-4. 



86. ,, „ ina3qualis, d'Orb., I. c, p. 30, pi. 651, 



figs. 5-8. 



87. „ cretacea, d'Orb., I. c, p. 63, pi. 600, figs. 17-19. 



88. „ regularis, d'Orb., I. c, p. 64, pi. 601, figs. 1-3. 



89. „ undata, d'Orb., I. c, p. 75, pi. 656 (fig. 11 only). 



90. „ Gandryana, d'Orb., I. c, p. 193, pi. 682, figs. 1-3. 



91. ,, areolata, Hag., 'Bryoz. der Maest. Kreideb.,' p. 60, 



pi. 6, fig. 12. 



1834. Genus Membeanipora, Blainville ('Terr. Cret.,' p. 539). 



Generic cliarader. — Zoarium encrusting or with an erect habit of 

 growth. ZocECiA irregularly disposed, occasionally in linear series. 

 Margins raised, front depressed, wholly or in part membranous. 



92. Membranipora granulosa, d'Orb. (Flustrellaria), ' Terr. Cret.,' p. 



52.3, pi. 725, fig. 2. 



93. „ confusa, d'Orb. (Flustrellaria), I c, p. 524, pi. 725, 



figs. 9-12. 



94. „ irregularis ? d'Orb. (Flustrina), I. c, p. 305, pi. 702, 



figs. 14-16. 



95. ,, marginata, d'Orb. (Semiflustrina), I. c, p. 579, 



pi. 733, figs. 5-8. 



96. ,, monihfera, d'Orb. (Semiflustrina), I. c, p. 577, 



pi. 732, figs. 6-9. 



97. ,, pulchella,d'Orb.,var. granulosa,newvar. See 'Terr. 



Cret.,' pi. 701, figs. 7-9 (Flustrina). In all pro- 

 bability d'Orbigny's figures are drawn from a 

 worn example of the species, whereas the British, 

 examples derived from the Chatham Chalk are 

 beautifully granulated on the marginal walls. 



' Fifth Report on Fossil Polyzoa. 



'^ Ann. de la Soc. Boy. Malacol. de Bclgiqve, 1886, tome xxi. 



