64 



I am suggesting the name of torri for this species, after 

 my friend Dr. W. G. Torr, to whom I am indebted for a good 

 deal of material I hope to deal with in a future paper. 



Addendum. 



Since writing the foregoing Dr. J. C. Verco has sent me 

 his stereoscopic microscope, and with the aid of this splendid 

 instrument the following additional observations have been 

 made: — 



The so-called scales, with which the girdle is clothed, are 

 of a distinct and peculiar character. The statement by Car- 

 penter, published by Dr. Pilsbry (Man. Con., pt. 56, p. 239), 

 that they "resemble grains of wheat set on end," is a very 

 good one; they are bilobed, and shaped like the blunt or 

 broad end of a grain of wheat, patches of them being level, 

 almost like a cobble pavement; other patches are irregular, 

 many standing up for more than half the length of the 

 "wheat-grain" above the normal level. These bilobed, grain- 

 like scales are, most of them, transparent and glassy; others, 

 again, are opaque and white, but still with a glass-like 

 appearance. 



Between these "wheat-grains" the strange "spear-heads" 

 push through and look like a cylindrical pointed spear-head 

 made of porcelain, and are, I estimate, eight times the length 

 of the scales. 



Later, as the "spear-head" is pushed forward, a pale- 

 brown, horny-looking tube, or stalk, is produced, which is 

 heretofore described as a coarse hair, for want of better term, 

 which, as .it lengthens, buds. First the porcelain "spear- 

 head" is produced, behind which the horny tube-like stem 

 widens by the addition of an extra flute, ultimately becoming 

 a distinct branch. In one or two instances a single stalk has 

 branched six times and been furnished with six "spear- 

 heads." These side branches are of a considerable length, 

 often several times the length of the spear-headed apex. L 

 believe the branches do not again bifurcate, although they 

 appear to do so, due to the fact that three or four of these 

 stalks come through the same aperture in the girdle, usually 

 side by side rather than in a circle, as do the spicules in 

 Acanthochitons. 



The tubes, or coarse hairs, are pale horn-colour, highly 

 polished, as if varnished, transversely striated; in some cases 

 the striae are near together, but more usually forming 

 somewhat distant rings for the whole length of the tube. In 

 a few instances these striae are absent; in others the sulcae 

 are broader and placed at greater distances, suggestive of 

 segments or the knodes of a plant. 



