A treatise on zoology . Fio. XXIX. Upward passage of anal (j) in Uloa-inus. 1, anal area of Ulocrlniis J:lniri; 2, posteriorview of U. liuttxl; 8 and 4, U. Kansusensis, tlie ctip from posterior and tioin above, x 3.(From Bather, after Jliller & Gnrley.) proximal plate of the median line of the anal tube, whatever itsposition. Modification of the cup is not confined to the fixed brachialsand interbrachials, but also affects the patina. We have discussedthe disappearance of IBB. We have also to note a tendency tofusion in the plates of the proximal circlet, whether IBB or BB,and their change of
A treatise on zoology . Fio. XXIX. Upward passage of anal (j) in Uloa-inus. 1, anal area of Ulocrlniis J:lniri; 2, posteriorview of U. liuttxl; 8 and 4, U. Kansusensis, tlie ctip from posterior and tioin above, x 3.(From Bather, after Jliller & Gnrley.) proximal plate of the median line of the anal tube, whatever itsposition. Modification of the cup is not confined to the fixed brachialsand interbrachials, but also affects the patina. We have discussedthe disappearance of IBB. We have also to note a tendency tofusion in the plates of the proximal circlet, whether IBB or BB,and their change of shape due to the introduction of anals into the. IKi. XXX. Mis^ratioM of tin- anal in Anti-ilnii. (Afb-r W. 11. Carpenter and M. Sars.) ()ri;;inatin^lietwecn llH, tli« plate r gradmilly moves n|)\\ards, fvcnlually atropliyin^ till only two smallfrannnMits remain at th«i Imse of the anal tiilx! (/), Tlie dotted lines in 1 show the course of thegut. Tliese figures also show change in shape of i:it, and ntropliy of omls (o). patina. The fiist stage is the fusion of one ]>air, })roducing 1largo and .{ small plates (Fig. XXXI. 2). This is almost entirelyrestiictcid to monocyclic genera, where the plates that fuse are thelight and left anterior basals. Next comes the fusion of two i>air,jnoducing 1 small and 2 large i)lates (Fig. XXXI. 3). This occursin both Mono- and Di-cyclica. In the fornu-r the small |)late isthe hift antciior basal, or rarely left ])osterior basal ; whereasin Kubbistoidea it is the right anterior basal (Fig. XXXI. 4).Ill Dicyclica throe infrabasals have boon observed only among THK CRINOIDEA 123 Tiijulunata J
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