JOUKNAL 



OF THE 



ROYAL MIOROSOOPIOAL SOCIETY. 



FEBRUAEY 1884. 



TEANSACTIONS OF THE SOCIETY. 



I. — The Constituents of 8ewage in the Mud of the Thames. 

 By Lionel S. Bealb, F.R.S., Treas. R.M.S. 



(Bead lOth January, 1884.) 

 Plates I. -IV. 



The particles constituting tlie cloud-like masses of dark-brown and 

 in some places black mud, held in suspension in the tidal water of 

 tbe Thames and carried backwards and forwards by the tide, and 

 which subside and form the soft mud which accumulates on the 

 surface of the submerged banks, have always afforded objects of 



EXPLANATION OF PLATES I.-IV. 

 Plate I. 



Fig. 1. — Objects in Mud from Crossness Southern Outfall. — a, muscular fibres 

 which have passed through the intestine and have been partly dissolved by the 

 digestive fluids, but which have undergone further disintegrative changes in con- 

 sequence of the prolonged action of the Thames water upon them. In many of 

 the muscular fibres the tranverse markings are still visible. At «** is seen a fibre in 

 which the transverse striae are very distinct, although the tissue is itself undergoing 

 disintegration, c*, a portion of a very small spiral fibre from vegetable tissue. 

 d, crystals of fatty acids formed by the decomposition and oxidation of fatty matter. 

 d*, a collection of particles of carbon, probably soot. /, portions of yellow elastic 

 tissue, probably from the areolar tissue of meat, h, portions of yellow fsecal matter in 

 various stages of disintegrative change. In some of these masses are seen minute 

 particles of sand and other matters which have adhered to the surface, or have 

 become mixed with the soft viscid matter, k, a small piece of mica. I, a portion of 

 myelin from nerve-tissue which has been long macerated in the Thames water, 

 m, collection of bacteria, w, bacteria in the shell of a diatom. 



Fig. 2. — Also from Crossness Southern Outfall. — c, large spiral vessels from vege- 

 table tissue (common cabbage), c**, two small spiral vessels still connected 

 together as in their natural position in the tissues of the plant. 



Fig. 3. — From a mud-bank off Erith. — d, crystals of fatty acids, the upper, rf 

 a collection of crystals of fatty acids, c?**, a mass composed principally of oil- 

 globules, with perhaps a little fsecal matter, h h, masses consisting of yellow fsecal 

 matter with a few oil-globules, i, a glistening mass of very hard fatty matter. 

 k, a minute fragment of mica. 



Ser. 2.— Vol. IV. B 



