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Show 1887.] MR. R. TRIMEN ON BIPALIUM KEWENSE. 549 plants) fully exposed to bright daylight. The only individual that broke up into short fragments was one which I wished to preserve, and to which I incautiously applied alcohol not sufficiently diluted. Multiplication by transverse fission is, however, well shown by this animal. The first that I had (about 8 inches long) on the third day of its captivity parted with a short portion (about | inch) of its body; and this portion, at first almost motionless, soon began very slowly to move, but remained sluggish and inactive ; on the fifth day a second portion was given off, about the same size as the first. O n the sixth day the parent worm unfortunately effected its escape, possibly through the perforated zinc covering of the jar, although the perforations were very small. To prevent the escape of the smaller ones I now put the stopper in the mouth of the jar. Two or three days afterwards I was surprised to find a third specimen, very much smaller than the others, but could not ascertain which of its two companions was its parent. The three all remained very sluggish for six days, but on February 4th the two larger ones were moving about; and on m y tilting the jar so as to let the water touch them, all three began gliding with some activity towards the, top of the jar. Although all three had by this time developed a small fan-shaped expansion at the cephalic extremity (which appeared to be entirely wanting on their original start as separate individuals), it was noticeable that they did not use it as the old worms perpetually do, viz. in exploring the way from side to side with ceaseless undulating motion of its free edge, but moved straight onward with the body simply extended. A living specimen about 6 inches in length, which was brought to me on the 30th ultimo, parted with about | inch of itself on the evening of the second instant. The separated portion was simply thicker and blunter at one end, but soon began to move in a straight line with the thicker end foremost. This separate individual has not up to date (13th May) shown much activity ; it usually remains near its parent in a slightly curved posture. The parent worm, like all the larger living specimens I have seen, assumes quite complicated coils (often about grass stems and leaves) when at rest; but I have specially remarked in this specimen that it also presents at times several spiral twists or contortions. On the 5th instant it remained for many hours so twisted, one spiral being at a little distance behind the head, another about an inch further down, and a third about 2 inches from the caudal extremity Without abundant moisture this Bipalium speedily dies. In spite of its copious supply of mucus, it would appear to be extraordinarily sensitive to the effect of contact with an injurious substance ; for a good-sized one brought to me on the 3rd instant died with remarkable suddenness on contact with the blacklead used for polishing grates. This specimen, in apparent vigour, was brought in while I was at breakfast, and was placed with the arum-leaf on which it rested on the mantlepiece. Not more than a quarter of an hour afterwards I rose to remove it, but it had left the leaf and could not for some ten minutes be found. It was then discovered, quite dead and |