. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 208 H. P. KJERSCHOW-AGERSBORG. madreporite is still in the interraditis of Ludwig. The posi- tion of the anus, in fact, corresponds, now, with Delage and Herouard's asteroid plan. Figure 2 is copied from Ritter and Crocker ('oo) and represents a diagram of the muscles of the aboral disk, seen from the inside, and as though looked down upon, showing the apical radial muscle bands, the madreporite, and the position of the anus close to the origin of the muscle of ray A (VI.). If ray A were the anterior end, then the anus
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 208 H. P. KJERSCHOW-AGERSBORG. madreporite is still in the interraditis of Ludwig. The posi- tion of the anus, in fact, corresponds, now, with Delage and Herouard's asteroid plan. Figure 2 is copied from Ritter and Crocker ('oo) and represents a diagram of the muscles of the aboral disk, seen from the inside, and as though looked down upon, showing the apical radial muscle bands, the madreporite, and the position of the anus close to the origin of the muscle of ray A (VI.). If ray A were the anterior end, then the anus would be anterior to the center of the dorsal side; but since ray A is, in fact,. A JF 1L B FIG. 5. Young individuals in the i2-rayed stage to show the interpolation zones: These figures are as per the original and show the reverse condition as in Fig. 4, which has been inverted to show the right relation of the madreporite to the true anterior end. A, oral view; B, aboral view. (From Ritter and Crocker.) the posterior ray, the anus becomes placed posterior to the mid- dorsal point. Delage and Herouard ('03) adopt Cuenot's plan ('91), with the madreporite in the interradius ; the anus in interradius , a little posterior of the mid-dorsal, but also a little to the right of the median line (Fig. 9). This seems to be an arbitrary matter of orienting the star. If the interradius of Cuenot is placed as anterior end, the anus comes in the similar position as in Ludwig's plan: the madreporite is in interradius III.; the anterior end is ray III. (Fig. 9). My drawing of the radial aboral muscles does not correspond at all with Ritter and Crocker's, in the point of orientation, and, in fact, also in the points relative to the general radiation of these muscles. I have com- pared the arrangement of the apical radial muscles in both large and small individuals having the same relative number of rays and. Please note that these images are extracted from s
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
