76 ZOOPHYTES. 



a certain breadth. In the annexed figure, a small cell between four 

 polyps belonged to a young polyp, which was one of these new buds. 

 The young continue enlarging, till the adult size is attained, and then 

 the intervals going on to increase, other buds open. The elevated 

 lines, which striate radiately the spaces between the cells or stars, 

 indicate what we have before stated, that the visceral lamellae are 

 prolonged beyond the visceral cavity, through the interstitial spaces 

 between adjoining polyps ; and it is possible that the new bud pro- 

 ceeds from one of these lamellae, though appearing at the middle of 

 the interstitial space. 



77. When the prolate growth is attended by a widening of the 

 disks, the buds, as stated, open in the widening disk. In the Mean- 

 drine zoophytes (plate 8, fig. 1, and plate 14), bud follows bud, and 

 the widening continues, until the disk, instead of being circular, as in 

 the Astrcea argus, or in the germ-polyp with which the Meandrina 

 commenced, has at last a long linear form, often very flexuous, and 

 contains a large number of polyp mouths; and, beneath, as many 

 polyp stomachs, all communicating apparently with the same vis- 

 ceral cavity, or connected with one another by a system of large 

 interlamellar spaces. In the Merulinse, we have foliaceous corals 

 illustrating well this mode of growth ; and they are the analogues, in 

 this division of the AstrseidiB, of the Echinopores, among the pre- 

 ceding. The lines of polyp mouths continue extending outward, 

 separated by narrow lamellate ridges, and the new buds open near 

 the margin of the folium, on the surface of the extending disks 

 (plate 15). 



b. The length of these meandering disks, and their flexuous furca- 

 tions, seem sometimes to be indefinite. Yet in other species they 

 have their limits. After elongating for a while, a ridge forms across, 

 and a subdivision is produced. The proper Astrseas, with prolate 

 disks, differ from the Meandrinas in this subdivision taking place 

 after the opening of each new mouth in the disk, in consequence of 

 which, the form may become a little oblong, but is soon restored to 

 a circular shape again. This is illustrated in the following figures, 

 which show the progress of external changes. 



The simple disk becomes oblong (fig. 36), and a new mouth opens. A 

 subdivision commences (fig. 37) as growth goes on, and finally the 

 disk entirely subdivides (fig. 38), and each part is surrounded by its own 

 circle of tentacles. This division appears to commence whenever the 

 number of lamella} which is constantly increasing has reached the 



