Miscellaneous. 161 



the animal measures from ^^ to ^^ of a line in diameter ; and the 

 zone is from ^\^ to .7^^ of u line wide. The species may be named 

 Amieba zona lis. 



The interesting researches of Prof. Richard Greef, of ilarburg, 

 published in the second volume of Schultze's * Archiv f. mikro- 

 skoi)ische Anatomic,' on Anuelnn living in the earth (" Ueber einigo 

 in der Erde lebendo Amoeben, &c."), led me to look in similar posi- 

 tions for llhizopods. 



In the earth, about the roots of mosses growing in the crevices 

 of the bricks of our city pavements, in damp places, besides finding 

 several species of Anueha, together with abundance of the common 

 whcel-animalcide, liollfcr imhjaris, I had the good fortune to dis- 

 cover a species of Gromia. I say good fortune ; for it is with the 

 utmost pleasure I have watched this cnrious creature for hours 

 together. The genus was discovered and well described by Du- 

 jardin from two species, one of which, 0. oviformis, was found in 

 the seas of Franco ; the other, the G, Jluviatilis, in the river 

 Seine. 



Imagine an animal, like one of our autumnal spiders, stationed 

 at the centre of its well-spread net ; imagine every thread of this 

 net to be a living extension of the animal, elongating, branching, 

 and becoming conllueut so as to form a most intricate net ; and 

 imagine every thread to exhibit actively moving currents of a viscid 

 liquid, both outward and inward, carrying along particles of food 

 and dirt, and you have some idea of the general character of a 

 Gro7nia. 



The Gromia of our pavements is a spherical cream-coloured body, 

 about Y^jj of a line in diameter. When detached from its posi- 

 tion and placed in water, in a few minutes it projects in aU direc- 

 tions a most wonderful and intricate net. Along the threads of this 

 net float minute Naviculce from the neighbourhood, like boats in the 

 current of a stream, until reaching the central mass they are there 

 swallowed. Particles of dirt are also collected from all directions, 

 and are accumulated around the animal ; and when the accumulation 

 is sufficient to protect it, the web is withdrawn, and nothing appa- 

 rently will again induce the animal to produce it. 



From these observations we may suppose that the Gromia terri- 

 coLA, as I propose to name the species, during dry weather remains 

 quiescent and concealed among accumulated dirt in the crevices of 

 our pavements, but that in rains or wet weather the little creature 

 puts forth its living net, which becomes so many avenues along 

 which food is conveyed to the body. As the neighbourhood becomes 

 dry, the net is withdrawn to await another rain. The animal with 

 its extended net can cover an area of nearly half a line in diameter. 

 The threads of the net are less than the g^^^-o^f of an inch in dia- 

 meter.— Proc. Acad. Nat. Sci. Phil. 1874, p. 88. 



Ann. & Mag. K Hint. Ser. 4. TV. xv. 11 



