1S87.] MR. R. TRIMEN ON BIPALIVIM KEWENSE. 549 



plants) fully exposed to bright daylight. The only individual that 

 broke up into sliort 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 bv 

 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. On the 

 sixth day the parent worm unfortunately effected its escape, possibly 

 through the perforated zinc covering of the jar, although the perfor- 

 ations 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 tiian 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 my tilting the jar so as to let tlie water touch them, 

 all three began gliding with some activity towards the top of thejar. 

 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 notice- 

 able 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 

 5lh 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 1 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 "^ 



