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Show 84 IIAD!TS OF WOUMS. CrrAP. II. 1nore resistance to being drawn in. If seized near the middle the triangle was doubled up, with the apex and base left sticking out of the tube. As the sides of the triangles were three inches in length, the result of their being drawn into a t.ube or into a burrow in different ways, may be conveniently divided into three groups: those drawn in by the apex or within au inch of it; those drawn in by the base or within an inch of it; and those drawn in by any point in the middle inch. In order to see how tho triangles would be seized by worms, some in a d~mp state were given to worms kept in confinement. They were seized in three different manners in the case of both the narrow and broad triangles: viz., by the margin ; by one of the three anO'les which was often completely engulfed b ' in their mouths; and lastly, by suction applied to any part of the flat surface. If lines parallel to the base and an inch a part, are drawn across a triangle with the ~ides three inches in length, it will be divided into three parts of equal length. Now if worms seized indifferently by chance any part, they would assuredly seize on the basal part or CHAP. II. 'I'liEIR IN'L'ELLIGENCE. 85 division far oftener than on ei tlter of the two other di vi ·ions. For the area of the basal to tho apical part is as 5 to l, so that the chance of tho former being drawn into a burrow Ly suction, will be as 5 to I, compared with the apical part. ~rho Lase offers two angles and the apex only one, so that tho former would have twice as good a chance (i1:dependently of tho size of tho angles) of bemg engulfed in a worm's mouth, as would the apex. It should, however, be stated that the apical angle is not often seized by worn1s; the margin at a little distance on either side being preferred. .[judge of this from havinO' found in 40 out of 46 cases in which trfangles l1ad been drawn into burrows by their apical ends, that the tip had been doubled back within the burrow for a length of between -.l th of an inch and I inch. Lastly, the proportion between the margins of the basal and apical parts is as 3 to 2 for the broad . ' and 2~ to 2 for the nalTOw triangles. From these several considerations it might certainly have been expected, supposing that worms seized hold of the triangles by chance, that a considerably larger proportion would have |