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jects frequently like a more than semiglobular, or even like a nearly pyramidal tubercle. 

 On closer inspection it will be found (see fig. 4) to consist as it were of 2 parts; only the 

 exterior, more salient part having the meandric furrows; while the other part is covered 

 with strong pointed spines, which also (in annular arrangements) encircle the more salient 

 part. The secretory pore situated on the dorsal side of the disc (the so-called anal aper- 

 ture) has the same somewhat excentric position as in the Br. coronata; and the disc exhi- 

 bits at this point a slight elevation (see fig. 2). I have not succeeded in discovering any 

 traces of pedicellaries on the dorsal side of the disc, where in the Br. coronata they are 

 always plainly apparent, The spines attached to the underside of the disc seem also to be 

 somewhat different from those of the Br. coronata, The furrow-spines on the lower side of 

 the adambulacral plates (see fig. 2, 3 & 5) are remarkably large, usually 12 for each inter- 

 radial space, of which 4 especially, on the interior adambulacral plate, are remarkably long 

 and strong, and directed inwards towards the oral aperture, whereby they appear to have 

 assumed the functions of the proper oral spines. These latter, 6 in number, are however 

 here (see fig. 9) extremely small and quite covered by the other spines: so that they do 

 not become apparent until the others are removed. The oral membrane resembles comple- 

 tely that of the Br. coronata (see fig. 5) but is in most captured individuals difficult to per- 

 ceive; as usually the folds of the stomach are evaginated a long way out of the mouth, 

 and the oral aperture itself strongly enlarged (see fig. 3). 



The arms (see fig. 1) have about the same length in proportion to the diameter of 

 the disc, and exhibit in their general form a great resemblance to those of the Br. coronata, 

 but are immediately distinguished by the absence of the elevated spines in annular arrange- 

 ment on the transversal ribs, which are so characteristic of the latter species. Likewise we 

 do not usually find any trace of the soft transverse ridges covered with pedicellaries, which 

 are so distinctly marked in the Br. coronata. Only in a few unusually large specimens 

 (see fig. 1) I have found slight indications of such ridges between the interior calcareous 

 ribs; while in the exterior part of the arm no such indications were apparent. With respect 

 to the calcareous ribs, they have in the Br. endecacnemos a relatively far greater extension 

 on the arms than in the Br. coronata, being apparent on all the interior half. Their num- 

 ber is therefore also much greater, namely 30—40, or about twice as great as in the Br. 

 coronata. In their shape and arrangement they correspond otherwise perfectly to those of 

 other species; and also in this they appear frequently variously sinuous and anastomosing 

 with each other. If we now examine these calcareous ribs with sufficient magnifying power, 

 we shall find on them, besides numerous pedicellaries, also a single row of extremely small 

 spines (see fig. 13). These spines are (fig. 14) compressed, lancet-formed, and, as it appears, 

 entirely without any cuticular sheath; neither do they appear to be movably articulated to 

 the calcareous rib, like those of the Br. coronata in the same place, but merely to repre- 

 sent simple processes of the same. The whole dorsal cuticle of the arms between the ribs 

 will also be found covered with similar, although somewhat longer and thinner, small micro- 



