S8 Canon A. M. Norman — Nnfes on the 



phiblcstrum behind, hut liere also extonding np the sides and 

 round the front, so that the membranous portion is completely 

 surrounded by it, and tlie calcareous portion sloping inwards 

 and downwards ; the membranous portion with the oral 

 opening is situated in a deep hollow. On the distal margin, 

 in the place usually occupied by the oral spines, a pair of 

 avicularia, with their pointed mandibles directed inwards 

 in such a way so that their tips nearly meet in the middle. 

 There are three pair of lateral pore-chambers and several 

 (four usually) lucid spots in the hind walh 



Antropora is remarkable on account of the most unusual 

 position of the avicularia transversely situated above the oral 

 opening. Avicularia occur on the sides of the oral opening 

 and sometimes appear above it (as iu Am.])liibh'strum Flevi- 

 itigii), but in this latter case they belong to the bottom of the 

 zocEcium above; here they are in the extreme upper part of the 

 zooecium. The back of the zooecium is characterized by three 

 pair of conspicuous pore- chambers, and on the anterior part 

 of the back wall, which is more thickened than the portion 

 posterior to it, are at the front two transparent bays, and 

 behind these a pair of round lucid spots, behind which again 

 are sometimes seen two others of much smaller size (fig. 4). 



The types were described by Hincks from specimens sent 

 to him from Madeira by Mr. J, Y. Johnson. In 1896 I 

 dredged it not rarely off that island in 70-100 fathoms, 

 encrusting small shells such as young Pectens, Venus medi- 

 (erranea, Dentalium, &c., and it especially affected fragments 

 of the coral Madracis aspernla. The polyzoon most commonly 

 associated with it was Onycliocella antiqaa, Busk. These species 

 often grew over each other, and were so curiously alike in 

 general form and appearance that the avicularia of u4w^ro/;orrt 

 were the available character for separating them with a hand- 

 lens. 



Genus Ammatophgra"^, gen. nov. (PL VIII. figs. 5, 6, 7.) 

 Type, Ammatoj^hora {Membranipora) nodulosa (Hincks). 



Memhrajiipora nodvlosa, Hiucks, Hist. Brit. JNIariue Polyzoa, p. 170, 

 pi. XX. lig. 9. 



Zooecia and ooecia depressed and flattened. Zooecia sub- 

 ovate ; a calcareous crest occupying about two-thirds of the 

 area. Oral opening at distal end of the membranous portion. 

 Walls thin, terminating at the ooecium in a knob. Ooccium 

 entirely separable from tlie zooecium, resting on the knol)s 

 just mentioned ; of unusual and varied form (see figures). 

 * (i^fxa, a Lnot, and cfjipco. 



