BULLETIN OF THE UNITED STATES FISH COMMISSION. 257 



Vol. IV, Tlo. 1 7. Washington, ». C. Jsaly 30, 188i. 



138.— A FIHH-EATIIVC; I»t.ANT. 



By G. E. SIMMS, Jr. 



[In the Fishing Gazette, May 31, 1884,] 



I have recently discovered amongst the aquatic weeds placed in my 

 aquarium, where I have also a large number of newly-hatched perch 

 and roach, a novel and unexpected enemy to the pisciculturist in the 

 bladder traps of Utricularia vuJgaris^ which is capable of catching and 

 killing young fry. 



My attention was first drawn to it by observing that several of the 

 tiny fish, without any apparent cause, were lying dead on the weeds, 

 while the rest of the brood looked perfectly healthy and in good condi- 

 tion. At first I was somewhat puzzled at the strange position in which 

 thay were lying, and in trying to move one with a small twig I was still 

 more surprised to find it was held fast by the head, in what I thought, 

 when I pulled the plant from the water, were the seed vessels; and a 

 still closer examination revealed the strange fact that others of the little 

 fish had been trapped by the tail, and in one or two instances the head 

 and tail of the same fish had been swallowed by adjacent bladders, thus 

 forming with its body a couDecting bar between the two. 



At first I was undecided how to act, for I could bring to memory no 

 instance in which I had seen the existence of a piscivorous plant — i. e., 

 one preying on vertebrates — recorded in any book I had ever read, and 

 I was unwilling to make such an assertion without the opinion of some 

 one better capable of forming a judgment on the subject than myself; 

 so I placed one or two good specimens in a glass jar and went to the 

 Museum, where I was fortunate enough to see Professor Moseley, who 

 immediately verified my suspicions. 



According to Bentham's Handbook of British Flowering Plants, the 

 Utricularia vulgaris, or greater bladderwort, is widely distributed over 

 Britain, and although it is local, yet where it is found it grows luxuri- 

 antly, seldom appearing in the rivers, but chiefly confining its presence 

 to still ponds and deep ditches, the places where it is most likely to 

 work mischief to the young fry. 



A peculiar fact in connection with it is that it has no roots at any 

 time of its life, and the floating, root-like branches which are covered 

 with numerous capillary and much divided leaves are interspersed with 

 tiny green vesicles, which were supposed by a former school of botanists 

 to be filled with water, by which means the j^lant was kept at the bot- 

 tom until tlie time of flowering, when the water gave place to air, and 

 the plant then rose to the surface to allow its bloom to expand. 



As a matter of fact, these vesicles exercised no such function, their 

 Bull. U. S. F. C, 84 17 



