. Bulletin of the British Museum (Natural History). 142 PITT AND TAYLOR. Figs 162-163 Echinocava raulinii (Michelin), Fig. 162, USNM 69903a, x 40; see also Fig. 161. Fig. 163, BM(NH) D57949; 163A, autozooecial fascicle, x 39; 163B, alveoli between fascicles, x 102; 163C, possible broken brood chamber attached to a fascicle, x 48. Paracrescis are features typifying lichenoporid rectangulates among living cyciostomes. However, the affinity of Para- crescis with the Lichenoporidae is difficult to demonstrate in the absence of well-preserved brood chambers. The brood chambers of lichenop
. Bulletin of the British Museum (Natural History). 142 PITT AND TAYLOR. Figs 162-163 Echinocava raulinii (Michelin), Fig. 162, USNM 69903a, x 40; see also Fig. 161. Fig. 163, BM(NH) D57949; 163A, autozooecial fascicle, x 39; 163B, alveoli between fascicles, x 102; 163C, possible broken brood chamber attached to a fascicle, x 48. Paracrescis are features typifying lichenoporid rectangulates among living cyciostomes. However, the affinity of Para- crescis with the Lichenoporidae is difficult to demonstrate in the absence of well-preserved brood chambers. The brood chambers of lichenoporids are roofed by highly perforate interior walls (see Hayward & Ryland 1985). A second possibility is that Paracrescis is more closely related to the cerioporine cyciostomes; brood chambers in the similar genus Crescis appear to be roofed by pseudoporous exterior wall. Finally, on the basis of the lunaria/pseudolunaria and extra- zooidal vesicles, Boardman (1984) believed Semicrescis, in which brood chambers are also unknown (E. Voigt, personal communication 1987), to be closely related to the Cystoporata, a stenolaemate order more usually regarded as exclusively Palaeozoic in its distribution. Paracrescis is here questionably assigned to the Family Lichenoporidae of the Suborder Rectangulata. Accordingly, the small apertures between the autozooecia are labelled as ?alveoli rather than kcnozooccia as they would be if Para- crescis were assigned to the Cerioporina. Range. Aptian. Paracrescis boardmanisp. nov. Figs 164-165 HOLOTYPE. BM(NH) D57711 (specimen and thin section), Little Coxwell Pit, Pitt Colin. Paratypes. BM(NH) D57712-3, Little Coxwell Pit, Davis Colin; D58207. west face of Badbury Hill, Faringdon, Pitt Colin. Name. For R. S. Boardman, in recognition of his major contributions to the study of stenolaemate bryozoans. Description. Zoarium encrusting, multilamellar with wide spaces often present between successive zoarial layers. The colony surface bears distinct
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