BLADDERWORTS AND THEIR BLADDERS. 13 
* Insectivorous Plants ” that they (the Utricularias) ‘commonly inhabit 
remarkably foul ditches.” Here, the water was bright, as was also the 
case in the only other place in which I have seen a Bladderwort growing, 
namely, in Connemara. It is also stated in the same work, on the 
authority of Warming, that ‘‘ they are quite destitute of roots even from 
the earliest period of growth, and float near the surface of the 
water.” These plants were certainly attached to the bottom. 
As to the presence of true roots I cannot speak with certainty, 
~as I had not read the above at the time, and did not pay sufficient 
note; but I brought away from the most shallow pool a piece of 
the turfy bottom undisturbed, on which two young plants were growing. 
They continued to grow when placed at the bottom of a glass vessel, 
about a foot below the surface, and never evinced any d sposition to float 
to the surface. But the Bladderworts seem more amenable to the attacks 
of both mollusks and confervee than any others of the small water plants 
in the same vessel, and the plants are consequently at present in a poor 
condition. Their gemme evidently have powers of resistance beyond the 
other portions of the plant, and will, I trust, grow next year. I should 
add, the observations recorded in ‘‘ Insectivorous Plants” have mostly 
reference to the species neglecta and vulgaris. 
An after-examination of the contents of the bladders by the microscope 
afforded a particularly interesting series of objects, the number and variety 
packed within some of them causing me to wonder how they could have got 
inside. HEntomostraca are prying and lively enough to penetrate into 
any odd corner; but in many of the other captives the power of loco- 
motion is at all events very slow and obscure. ‘There are, it is true, two 
long bristles or antenne that spring from either side of the valvular 
opening of each bladder, and these may act as guides to it, whilst the 
numerous short bristles surrounding the entrance prevent escape. The long 
antennee in some bladders project directly forward from the bladder, and 
in others are bent round underneath. There were bubbles of air in many 
of the bladders. The foreign contents were largely living, but also dead 
and decomposed in the state of a sort of muddy pabulum. . With the 
assistance of my friend, Mr. J. HK. Bagnall, the following list of the 
contents has been drawn up :— 
VEGETABLE Forms.—Motile forms of a unicellular alga very like 
Protococcus. A unicellular alga like Pleurococcus in series of four cells, 
the inner portion green, the outer part of the cells hyaline. Amongst 
Desmids: Cosmarium in conjugation, three species of Closterium—some 
of the bladders contained a large number of these; Penium, Euastrum, 
Ankistrodesmus, Micrasterias frequent. Of Diatoms: Meridion cireulare, 
species of Naviculare and others. Cells of algae, Tyndaridea, and others. 
Aynimat Forms.—Of Rhizopods: Difflugia abundant in one bladder, 
Arcella, and a peculiar bowl-shaped species. Of Entomostraca: Alonaovata, 
numerous and lively ; Cypris, Cyclops, Daphnia. Rotifers: R. vulgaris, 
and other species. Infusoria: Chilodon and Paramecium. Ofthesmaller 
algse, and Desmids particularly, various stages of growth were represented. 
Probably more time and research would have resulted in a yet larger list 
of prisoners. The bladders of U. minor, not only from being most 
numerous, yielded the best results. I was surprised at the large propor- 
tion of animals in a living, or at all events undecayed condition. Some 
of the Crustaceans must have lived inside the bladders for many days if 
not a week or more. For instance, the Alona ovata, which as far as my 
knowledge went did not exist in the water in which the plants were placed 
away from other plants. I may add that perhaps a month afterwards I 
examined three bladders that had been detached and remained at the 
bottom of the bottle. The walls had become very thin, but had retained 
