126 PROF. F. J. BELL ON AN ABNORMAL 



deepish canal turning in bebind the pillar. Outer lip not ex- 

 panded above, and but little so on the base ; strongly furrowed 

 by the spirals of the sculpture. Pillar short, stoutish, well 

 rounded, fine-edged, obliquely truncate, and sharp-pointed. Inner 

 lip a thin glaze on the body, but becoming thicker toward the 

 point of the pillar. H. 0*173. B. 0*04. Penultimate whorl, 

 height 0-02. Mouth, length 0-029, breadth 0015. 



This species seems to be somewhat variable in size, one of the 

 five specimens which represent it being a good deal larger than 

 the rest, with the same number of whorls. Another specimen is 

 more dumpily conical. 



It has some resemblance in a general way to 0. metaxa, della 

 Chiaje, but in that the contour lines are more regularly conical, 

 the spire is not at all scalar, the whorls are convexly rounded, 

 there is no deep sutural furrow, the tuberculations are long 

 across the shell, and each whorl has four, not three spirals ; the 

 form of the base is a good deal like, but the pillar is shorter, 

 stronger, straighter, rounder, and has not the sharp flanged edge 

 of that species. Prom C. tubercularis, Mont., which it resembles 

 in sculpture, it differs not only in its slender form, but in the 

 absence of the circumcolumnar thread on the base. 



Note on an Abnormal (Quadriradiate) Specimen of Amhlypneustes 

 formosus. By Prof. E. Jeffrey Bell, M.A., E.R.M.S. 



[Read April 15, 1880]. 



(Plate V.) 



It is now forty-three years since that accurate and painstaking 

 zoologist Rudolph Philippi described a monstrous sjDecimen of 

 Echinus melo *, which was especially remarkable for the excentric 

 position of the mouth and of the anus, and for the almost com- 

 plete disappearance of one of the five segments of which the test 

 of every Echinid is typically composed. Being at present en- 

 gaged in an examination of the group to which the name of 

 Temnopleuridse has been applied, I have, among others, taken in 

 hand the three specimens of Amhlypneustes formosus^ which, named 

 by Prof. Alex. Agassiz, have come as an earnest of the harvest of 

 the ' Challenger ' Expedition. The smallest of these at once 

 arrested my attention by the curious asymmetry which revealed 

 * Arch, fur Naturges. iii. (1837), p. 241, p]» v. 



